---------------------------------------
                                         OMB Number:                   3235-0006
                                         Expires:              December 31, 2006
                                         Estimated average burden
                                           hours per response ............. 22.8
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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    Form 13F

                               Form 13F COVER PAGE


Report for the Calendar Year or Quarter Ended:   March 31, 2006
                                                ------------------

Check here if Amendment [ ]; Amendment Number:
                                                  ------------
  This Amendment (Check only one.): [ ]  is a restatement.
                                    [ ]  adds new holdings entries.


Institutional Investment Manager Filing this Report:

Name:     Hennessy Advisors, Inc.
Address:  The Courtyard Square
          750 Grant Avenue, Suite 100
          Novato, CA  94945

Form 13F File Number:  028-06715

The institutional investment manager filing this report and the person by whom
it is signed hereby represent that the person signing the report is authorized
to submit it, that all information contained herein is true, correct and
complete, and that it is understood that all required items, statements,
schedules, lists, and tables, are considered integral parts of this form.

Person Signing this Report on Behalf of Reporting Manager:

Name:     Teresa M. Nilsen
Title:    Executive Vice President and Chief Financial Officer
Phone:    (415) 899-1555

Signature, Place, and Date of Signing:


/s/ Teresa M. Nilsen                  Novato, CA                  April 17, 2006
--------------------------------------------------------------------------------
Teresa M. Nilsen                      City, State                      Date


Report Type  (Check only one):

[X]  13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager
     are reported in this report.)

[ ]  13F NOTICE. (Check here if no holdings reported are in this report, and all
     holdings are reported by other reporting manager(s).)

[ ]  13F COMBINATION REPORT. (Check here if a portion of the holdings for this
     reporting manager are reported in this report and a portion are reported by
     other reporting manager(s).)






                              FORM 13F SUMMARY PAGE



Report Summary:


Number of Other Included Managers:                              0
                                                 ----------------------

Form 13F Information Table Entry Total:                       169
                                                 ----------------------

Form 13F Information Table Value Total:                $2,195,396
                                                 ----------------------
                                                       (thousands)



List of Other Included Managers:  NONE







Page 1 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
A T & T INC               COMMON     00206R102      11,775   435,483 SH      SOLE                            427,225        8,258
----------------------------------------------------------------------------------------------------------------------------------
AAR CORP                  COMMON     000361105      26,182   919,300 SH      SOLE                            919,300            0
----------------------------------------------------------------------------------------------------------------------------------
ADVANCE AUTO PARTS INC    COMMON     00751Y106       4,347   104,400 SH      SOLE                            104,400            0
----------------------------------------------------------------------------------------------------------------------------------
AETNA INC                 COMMON     00817Y108       5,327   108,400 SH      SOLE                            108,400            0
----------------------------------------------------------------------------------------------------------------------------------
ALBERTSONS INC            COMMON     013104104       3,843   149,700 SH      SOLE                            149,700            0
----------------------------------------------------------------------------------------------------------------------------------
ALERIS INTERNATIONAL INC  COMMON     014477103      32,370   673,400 SH      SOLE                            673,400            0
----------------------------------------------------------------------------------------------------------------------------------
ALLEGHENY TECHNOLOGIES
INC                       COMMON     01741R102      48,987   800,700 SH      SOLE                            800,700            0
----------------------------------------------------------------------------------------------------------------------------------
ALTRIA GROUP INC          COMMON     02209S103      10,483   147,942 SH      SOLE                            147,500          442
----------------------------------------------------------------------------------------------------------------------------------
AMERCO                    COMMON     023586100      41,290   417,200 SH      SOLE                            417,200            0
----------------------------------------------------------------------------------------------------------------------------------
ANDERSONS INC             COMMON     034164103      10,295   131,600 SH      SOLE                            131,600            0
----------------------------------------------------------------------------------------------------------------------------------
ASTEC INDUSTRIES INC      COMMON     046224101      24,681   687,500 SH      SOLE                            687,500            0
----------------------------------------------------------------------------------------------------------------------------------
BADGER METER INC          COMMON     056525108       6,273   110,100 SH      SOLE                            110,100            0
----------------------------------------------------------------------------------------------------------------------------------
BANCO BRADESCO SA          ADR       059460303      25,288   704,200 SH      SOLE                            704,200            0
----------------------------------------------------------------------------------------------------------------------------------
BANCO ITAU HLDG FINCIERA   ADR       059602201      25,352   851,600 SH      SOLE                            851,600            0
----------------------------------------------------------------------------------------------------------------------------------
BANK of AMERICA CORP      COMMON     060505104       3,969    87,151 SH      SOLE                             75,600       11,551
----------------------------------------------------------------------------------------------------------------------------------
BEACON ROOFING SUPPLY INC COMMON     073685109      30,464   749,600 SH      SOLE                            749,600            0
----------------------------------------------------------------------------------------------------------------------------------
BELLSOUTH CORP            COMMON     079860102       4,485   129,438 SH      SOLE                            125,700        3,738
----------------------------------------------------------------------------------------------------------------------------------
BERKLEY (W R) CORP        COMMON     084423102      26,533   457,000 SH      SOLE                            457,000            0
----------------------------------------------------------------------------------------------------------------------------------
BP PLC  -ADS               ADR       055622104       4,011    58,188 SH      SOLE                             51,700        6,488
----------------------------------------------------------------------------------------------------------------------------------
BRIGHTPOINT INC           COMMON     109473405      36,235 1,166,600 SH      SOLE                          1,166,600            0
----------------------------------------------------------------------------------------------------------------------------------
BRISTOL MYERS SQUIBB      COMMON     110122108       4,007   162,800 SH      SOLE                            162,000          800
----------------------------------------------------------------------------------------------------------------------------------





Page 2 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
BUILDING MATERIALS HLDG
CP                        COMMON     120113105       5,239   146,800 SH      SOLE                            146,800            0
----------------------------------------------------------------------------------------------------------------------------------
BURLINGTON COAT FACTORY
WRHS                      COMMON     121579106       4,745   104,400 SH      SOLE                            104,400            0
----------------------------------------------------------------------------------------------------------------------------------
CB RICHARD ELLIS GROUP
INC                       COMMON     12497T101      20,651   255,900 SH      SOLE                            248,900        7,000
----------------------------------------------------------------------------------------------------------------------------------
CHEMED CORP               COMMON     16359R103       6,373   107,400 SH      SOLE                            107,400            0
----------------------------------------------------------------------------------------------------------------------------------
CHEVRONTEXACO CORP        COMMON     166764100       4,322    74,557 SH      SOLE                             59,000       15,557
----------------------------------------------------------------------------------------------------------------------------------
CHILDRENS PLACE RETAIL
STRS                      COMMON     168905107       5,448    94,100 SH      SOLE                             94,100            0
----------------------------------------------------------------------------------------------------------------------------------
CHUNGHWA TELECOM CO        ADR       17133Q205       3,840   196,000 SH      SOLE                            196,000            0
----------------------------------------------------------------------------------------------------------------------------------
CIRCUIT CITY STORES INC   COMMON     172737108      23,567   962,700 SH      SOLE                            962,700            0
----------------------------------------------------------------------------------------------------------------------------------
CITIGROUP INC             COMMON     172967101      10,473   221,750 SH      SOLE                            221,750            0
----------------------------------------------------------------------------------------------------------------------------------
CLEAN HARBORS INC         COMMON     184496107       5,726   193,000 SH      SOLE                            193,000            0
----------------------------------------------------------------------------------------------------------------------------------
CLEVELAND-CLIFFS INC      COMMON     185896107       6,839    78,500 SH      SOLE                             78,500            0
----------------------------------------------------------------------------------------------------------------------------------
CMS ENERGY CORP           COMMON     125896100       5,434   419,600 SH      SOLE                            419,600            0
----------------------------------------------------------------------------------------------------------------------------------
COCA-COLA COMPANY         COMMON     191216100       4,270   101,975 SH      SOLE                            101,975            0
----------------------------------------------------------------------------------------------------------------------------------
COMMERCIAL METALS         COMMON     201723103      11,169   208,800 SH      SOLE                            208,800            0
----------------------------------------------------------------------------------------------------------------------------------
CONAGRA FOODS INC         COMMON     205887102       3,700   172,400 SH      SOLE                            172,400            0
----------------------------------------------------------------------------------------------------------------------------------
CONN'S INC                COMMON     208242107      19,553   572,400 SH      SOLE                            572,400            0
----------------------------------------------------------------------------------------------------------------------------------
DAIMLERCHRYSLER AG         ADR    sedol - 2307389    3,892    67,800 SH      SOLE                             67,800            0
----------------------------------------------------------------------------------------------------------------------------------
DENNYS CORP               COMMON     24869P104       3,951   830,000 SH      SOLE                            830,000            0
----------------------------------------------------------------------------------------------------------------------------------
DIAGEO PLC                 ADR       25243Q205       3,692    58,200 SH      SOLE                             58,200            0
----------------------------------------------------------------------------------------------------------------------------------
DONNELLEY (R R) & SONS CO COMMON     257867101       3,311   101,200 SH      SOLE                            101,200            0
----------------------------------------------------------------------------------------------------------------------------------
DOW CHEMICAL              COMMON     260543103       3,155    77,700 SH      SOLE                             77,700            0
----------------------------------------------------------------------------------------------------------------------------------




Page 3 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
DRESS BARN INC            COMMON     261570105      28,602   596,500 SH      SOLE                            596,500            0
----------------------------------------------------------------------------------------------------------------------------------
DREW INDUSTRIES INC       COMMON     26168L205      27,548   774,900 SH      SOLE                            774,900            0
----------------------------------------------------------------------------------------------------------------------------------
DU PONT (E I) DE NEMOURS  COMMON     263534109      10,351   245,225 SH      SOLE                            245,225            0
----------------------------------------------------------------------------------------------------------------------------------
EMCOR GROUP INC           COMMON     29084Q100      30,317   610,500 SH      SOLE                            610,500            0
----------------------------------------------------------------------------------------------------------------------------------
EMERSON ELECTRIC          COMMON     291011104       1,719    20,550 SH      SOLE                                  0       20,550
----------------------------------------------------------------------------------------------------------------------------------
ESCALA GROUP INC          COMMON     29605W107      27,740 1,059,200 SH      SOLE                          1,059,200            0
----------------------------------------------------------------------------------------------------------------------------------
EXPRESS SCRIPTS INC       COMMON     302182100      32,954   374,900 SH      SOLE                            374,900            0
----------------------------------------------------------------------------------------------------------------------------------
EXXON MOBIL CORPORATION   COMMON     30231G102         396     6,502 SH      SOLE                                  0        6,502
----------------------------------------------------------------------------------------------------------------------------------
FEDERAL HOME LOAN MORTG
CORP                      COMMON     313400301       3,337    54,700 SH      SOLE                             54,700            0
----------------------------------------------------------------------------------------------------------------------------------
FLOWSERVE CORP            COMMON     34354P105      11,335   194,300 SH      SOLE                            194,300            0
----------------------------------------------------------------------------------------------------------------------------------
FORD MOTOR CO             COMMON     345370860       3,379   424,446 SH      SOLE                            424,200          246
----------------------------------------------------------------------------------------------------------------------------------
FOSTER WHEELER LTD        COMMON    sedol B04MB31   26,252   554,900 SH      SOLE                            554,900            0
----------------------------------------------------------------------------------------------------------------------------------
FRONTIER OIL CORP         COMMON     35914P105      50,483   850,600 SH      SOLE                            850,600            0
----------------------------------------------------------------------------------------------------------------------------------
GEHL CO                   COMMON     368483103       5,730   173,000 SH      SOLE                            173,000            0
----------------------------------------------------------------------------------------------------------------------------------
GENERAL CABLE CORP/DE     COMMON     369300108      32,213 1,062,100 SH      SOLE                          1,062,100            0
----------------------------------------------------------------------------------------------------------------------------------
GENERAL ELECTRIC CO.      COMMON     369604103       2,676    76,950 SH      SOLE                             75,725        1,225
----------------------------------------------------------------------------------------------------------------------------------
GENERAL MOTORS CORP       COMMON     370442105       8,807   414,039 SH      SOLE                            413,675          364
----------------------------------------------------------------------------------------------------------------------------------
GENESCO INC               COMMON     371532102       4,577   117,700 SH      SOLE                            117,700            0
----------------------------------------------------------------------------------------------------------------------------------
GIANT INDUSTRIES INC      COMMON     374508109      28,240   406,100 SH      SOLE                            406,100            0
----------------------------------------------------------------------------------------------------------------------------------
GLAXOSMITHKLINE PLC        ADR       37733W105       3,583    68,500 SH      SOLE                             68,500            0
----------------------------------------------------------------------------------------------------------------------------------
GOODYEAR TIRE & RUBBER CO COMMON     382550101       6,355   438,900 SH      SOLE                            438,900            0
----------------------------------------------------------------------------------------------------------------------------------





Page 4 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
GREAT ATLANTIC & PAC TEA
CO                        COMMON     390064103      32,150   920,400 SH      SOLE                            920,400            0
----------------------------------------------------------------------------------------------------------------------------------
HEALTHCARE SERVICES GROUP COMMON     421906108       4,759   222,800 SH      SOLE                            222,800            0
----------------------------------------------------------------------------------------------------------------------------------
HEINZ (H J) CO            COMMON     423074103       3,826   100,900 SH      SOLE                            100,900            0
----------------------------------------------------------------------------------------------------------------------------------
HENNESSY ADVISORS INC     COMMON     425885100      49,849 1,846,270 SH      SOLE                                  0     1,846,270
----------------------------------------------------------------------------------------------------------------------------------
HOLLY CORP                COMMON     435758305      41,952   566,000 SH      SOLE                            566,000            0
----------------------------------------------------------------------------------------------------------------------------------
HOVNANIAN ENTRPRS INC     CLASS A    442487203       3,044    69,300 SH      SOLE                             69,300            0
----------------------------------------------------------------------------------------------------------------------------------
HSBC HOLDINGS PLC          ADR       404280406       3,619    43,200 SH      SOLE                             43,200            0
----------------------------------------------------------------------------------------------------------------------------------
HUMANA INC                COMMON     444859102      13,331   253,200 SH      SOLE                            253,200            0
----------------------------------------------------------------------------------------------------------------------------------
ING GROEP NV               ADR       456837103       4,027   102,200 SH      SOLE                            102,200            0
----------------------------------------------------------------------------------------------------------------------------------
INTL PAPER CO             COMMON     460146103       3,557   102,900 SH      SOLE                            102,600          300
----------------------------------------------------------------------------------------------------------------------------------
IPSCO INC                  ADR       462622101      29,343   281,900 SH      SOLE                            281,900            0
----------------------------------------------------------------------------------------------------------------------------------
J P MORGAN CHASE & CO     COMMON     46625H100      11,661   280,040 SH      SOLE                            279,750          290
----------------------------------------------------------------------------------------------------------------------------------
JABIL CIRCUIT INC         COMMON     466313103      26,273   613,000 SH      SOLE                            613,000            0
----------------------------------------------------------------------------------------------------------------------------------
JACOBS ENGINEERING GROUP
INC                       COMMON     469814107       8,839   101,900 SH      SOLE                            101,900            0
----------------------------------------------------------------------------------------------------------------------------------
JLG INDUSTRIES INC        COMMON     466210101      51,167 1,661,800 SH      SOLE                          1,661,800            0
----------------------------------------------------------------------------------------------------------------------------------
KB HOME                   COMMON     48666K109       3,957    60,900 SH      SOLE                             60,900            0
----------------------------------------------------------------------------------------------------------------------------------
KIMBERLY-CLARK CORP       COMMON     494368103       3,510    60,726 SH      SOLE                             59,600        1,126
----------------------------------------------------------------------------------------------------------------------------------
KRAFT FOODS INC           COMMON     50075N104       3,601   118,800 SH      SOLE                            118,800            0
----------------------------------------------------------------------------------------------------------------------------------
LABOR READY INC           COMMON     505401208       6,323   264,000 SH      SOLE                            264,000            0
----------------------------------------------------------------------------------------------------------------------------------
LENNOX INTERNATIONAL INC  COMMON     526107107       7,698   257,800 SH      SOLE                            257,800            0
----------------------------------------------------------------------------------------------------------------------------------
LILLY (ELI) & CO          COMMON     532457108       3,595    65,000 SH      SOLE                             65,000            0
----------------------------------------------------------------------------------------------------------------------------------



Page 5 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
LINCOLN NATIONAL CORP     COMMON     534187109       3,663    67,100 SH      SOLE                             67,100            0
----------------------------------------------------------------------------------------------------------------------------------
LONGS DRUG STORES CORP    COMMON     543162101       4,799   103,700 SH      SOLE                            103,700            0
----------------------------------------------------------------------------------------------------------------------------------
LUBYS INC                 COMMON     549282101       4,659   373,000 SH      SOLE                            373,000            0
----------------------------------------------------------------------------------------------------------------------------------
LUFKIN INDUSTRIES INC     COMMON     549764108       6,830   123,200 SH      SOLE                            123,200            0
----------------------------------------------------------------------------------------------------------------------------------
LYONDELL CHEMICAL CO      COMMON     552078107       2,764   138,900 SH      SOLE                            138,900            0
----------------------------------------------------------------------------------------------------------------------------------
MANITOWOC CO              COMMON     563571108      35,302   387,300 SH      SOLE                            387,300            0
----------------------------------------------------------------------------------------------------------------------------------
MARATHON OIL CORP         COMMON     565849106      24,816   325,800 SH      SOLE                            325,800            0
----------------------------------------------------------------------------------------------------------------------------------
MATTEL INC                COMMON     577081102       3,813   210,300 SH      SOLE                            210,300            0
----------------------------------------------------------------------------------------------------------------------------------
MCDERMOTT INTL INC        COMMON     580037109      10,122   185,900 SH      SOLE                            185,900            0
----------------------------------------------------------------------------------------------------------------------------------
MEADWESTVACO CORP         COMMON     583334107       3,359   123,000 SH      SOLE                            123,000            0
----------------------------------------------------------------------------------------------------------------------------------
MENS WEARHOUSE INC        COMMON     587118100       4,647   129,300 SH      SOLE                            129,300            0
----------------------------------------------------------------------------------------------------------------------------------
MERCK & CO                COMMON     589331107      12,157   345,067 SH      SOLE                            344,375          692
----------------------------------------------------------------------------------------------------------------------------------
MERITAGE HOMES CORP       COMMON     59001A102       3,100    56,400 SH      SOLE                             56,400            0
----------------------------------------------------------------------------------------------------------------------------------
MULTI-FINELINE ELECTRON
INC                       COMMON     62541B101      14,248   243,600 SH      SOLE                            243,600            0
----------------------------------------------------------------------------------------------------------------------------------
NATIONAL CITY CORP        COMMON     635405103       3,528   101,100 SH      SOLE                            101,100            0
----------------------------------------------------------------------------------------------------------------------------------
NORDSTROM INC             COMMON     655664100      22,775   581,300 SH      SOLE                            581,300            0
----------------------------------------------------------------------------------------------------------------------------------
NS GROUP, INC.            COMMON     628916108       6,200   134,700 SH      SOLE                            134,700            0
----------------------------------------------------------------------------------------------------------------------------------
OFFICE DEPOT INC          COMMON     676220106       8,561   229,900 SH      SOLE                            229,900            0
----------------------------------------------------------------------------------------------------------------------------------
OIL STATES INTL INC       COMMON     678026105      29,815   809,100 SH      SOLE                            809,100            0
----------------------------------------------------------------------------------------------------------------------------------
ON SEMICONDUCTOR CORP     COMMON     682189105      24,311 3,348,600 SH      SOLE                          3,348,600            0
----------------------------------------------------------------------------------------------------------------------------------
P G & E CORP              COMMON     69331C108         234     6,005 SH      SOLE                                  0        6,005
----------------------------------------------------------------------------------------------------------------------------------




Page 6 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
PALM INC                  COMMON     696643105      30,590 1,320,800 SH      SOLE                          1,320,800            0
----------------------------------------------------------------------------------------------------------------------------------
PANTRY INC                COMMON     698657103      34,065   546,000 SH      SOLE                            546,000            0
----------------------------------------------------------------------------------------------------------------------------------
PAPA JOHNS INTERNATIONAL
INC                       COMMON     698813102      23,124   704,800 SH      SOLE                            704,800            0
----------------------------------------------------------------------------------------------------------------------------------
PAR TECHNOLOGY CORP       COMMON     698884103       4,031   227,250 SH      SOLE                            227,250            0
----------------------------------------------------------------------------------------------------------------------------------
PAYLESS SHOESOURCE INC    COMMON     704379106      22,521   983,900 SH      SOLE                            983,900            0
----------------------------------------------------------------------------------------------------------------------------------
PETRO-CANADA               ADR       71644E102      25,960   545,500 SH      SOLE                            545,500            0
----------------------------------------------------------------------------------------------------------------------------------
PFIZER INC                COMMON     717081103      11,089   445,000 SH      SOLE                            442,900        2,100
----------------------------------------------------------------------------------------------------------------------------------
PHILLIPS-VAN HEUSEN CORP  COMMON     718592108       5,151   134,800 SH      SOLE                            134,800            0
----------------------------------------------------------------------------------------------------------------------------------
PIONEER COS INC           CLASS A    723643300       6,185   202,800 SH      SOLE                            202,800            0
----------------------------------------------------------------------------------------------------------------------------------
PITNEY BOWES INC          COMMON     724479100       3,563    83,000 SH      SOLE                             83,000            0
----------------------------------------------------------------------------------------------------------------------------------
PLAYTEX PRODUCTS INC      COMMON     72813P100      18,226 1,740,800 SH      SOLE                          1,740,800            0
----------------------------------------------------------------------------------------------------------------------------------
PLEXUS CORP               COMMON     729132100      36,950   983,500 SH      SOLE                            983,500            0
----------------------------------------------------------------------------------------------------------------------------------
PNC FINANCIAL SVCS GROUP
INC                       COMMON     693475105       3,655    54,300 SH      SOLE                             54,300            0
----------------------------------------------------------------------------------------------------------------------------------
PPG INDUSTRIES INC        COMMON     693506107       3,769    59,500 SH      SOLE                             59,500            0
----------------------------------------------------------------------------------------------------------------------------------
QUANEX CORP               COMMON     747620102      12,853   192,900 SH      SOLE                            192,900            0
----------------------------------------------------------------------------------------------------------------------------------
QUANTA SERVICES INC       COMMON     74762E102      36,809 2,297,700 SH      SOLE                          2,297,700            0
----------------------------------------------------------------------------------------------------------------------------------
REGIONS FINL CORP         COMMON     7591EP100       3,612   102,700 SH      SOLE                            102,700            0
----------------------------------------------------------------------------------------------------------------------------------
RELIANCE STEEL & ALUMINUM
CO                        COMMON     759509102      33,680   358,600 SH      SOLE                            358,600            0
----------------------------------------------------------------------------------------------------------------------------------
REYNOLDS AMERICAN INC     COMMON     761713106       3,956    37,500 SH      SOLE                             37,500            0
----------------------------------------------------------------------------------------------------------------------------------
RIVIERA HOLDINGS CORP     COMMON     769627100       3,176   188,500 SH      SOLE                            188,500            0
----------------------------------------------------------------------------------------------------------------------------------
RYERSON INC               COMMON     78375P107      23,204   867,100 SH      SOLE                            867,100            0
----------------------------------------------------------------------------------------------------------------------------------



Page 7 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
RYLAND GROUP INC          COMMON     783764103       4,199    60,500 SH      SOLE                             60,500            0
----------------------------------------------------------------------------------------------------------------------------------
SARA LEE CORP             COMMON     803111103       3,478   194,528 SH      SOLE                            193,300        1,228
----------------------------------------------------------------------------------------------------------------------------------
SEABOARD CORP             COMMON     811543107       4,304     2,700 SH      SOLE                              2,700            0
----------------------------------------------------------------------------------------------------------------------------------
SEARS HOLDINGS CORP       COMMON     812350106       3,915    29,700 SH      SOLE                             29,700            0
----------------------------------------------------------------------------------------------------------------------------------
SHAW GROUP INC            COMMON     820280105      15,030   494,400 SH      SOLE                            494,400            0
----------------------------------------------------------------------------------------------------------------------------------
SIERRA PACIFIC RESOURCES  COMMON     826428104       6,281   454,800 SH      SOLE                            454,800            0
----------------------------------------------------------------------------------------------------------------------------------
SIX FLAGS INC             COMMON     83001P109      23,126 2,271,700 SH      SOLE                          2,271,700            0
----------------------------------------------------------------------------------------------------------------------------------
SKYWEST INC               COMMON     830879102       7,464   255,000 SH      SOLE                            255,000            0
----------------------------------------------------------------------------------------------------------------------------------
SPARTAN STORES INC        COMMON     846822104       3,963   310,800 SH      SOLE                            310,800            0
----------------------------------------------------------------------------------------------------------------------------------
STANDARD PACIFIC CP       COMMON     85375C101       3,463   103,000 SH      SOLE                            103,000            0
----------------------------------------------------------------------------------------------------------------------------------
STOLT OFFSHORE S A         ADR       861567105       7,443   480,500 SH      SOLE                            480,500            0
----------------------------------------------------------------------------------------------------------------------------------
SUNOCO INC                COMMON     86764P109      20,409   263,100 SH      SOLE                            263,100            0
----------------------------------------------------------------------------------------------------------------------------------
SYKES ENTERPRISES INC     COMMON     871237103       6,646   468,700 SH      SOLE                            468,700            0
----------------------------------------------------------------------------------------------------------------------------------
SYNAGRO TECHNOLOGIES INC  COMMON     871562203       4,565   913,000 SH      SOLE                            913,000            0
----------------------------------------------------------------------------------------------------------------------------------
TELEFONIA DE ARGENTINA
CONT                       ADR       879991024           0    12,900 SH      SOLE                             12,900            0
----------------------------------------------------------------------------------------------------------------------------------
TELEFONICA DE ARGENTINA
CONT                       ADR       879991016           0    12,900 SH      SOLE                             12,900            0
----------------------------------------------------------------------------------------------------------------------------------
TELEFONOS DE MEX           ADR       879403780       3,372   150,000 SH      SOLE                            150,000            0
----------------------------------------------------------------------------------------------------------------------------------
TESORO PETROLEUM CORP     COMMON     881609101      23,536   344,400 SH      SOLE                            344,400            0
----------------------------------------------------------------------------------------------------------------------------------
THE CHARLES SCHWAB CORP   COMMON     808513105         174    10,100 SH      SOLE                                  0       10,100
----------------------------------------------------------------------------------------------------------------------------------
TRAMMELL CROW CO          COMMON     89288R106       6,522   182,900 SH      SOLE                            182,900            0
----------------------------------------------------------------------------------------------------------------------------------
TRANSMONTAIGNE INC        COMMON     893934109       3,847   392,200 SH      SOLE                            392,200            0
----------------------------------------------------------------------------------------------------------------------------------




Page 8 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
----------------------------------------------------------------------------------------------------------------------------------
                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
----------------------------------------------------------------------------------------------------------------------------------
                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
----------------------------------------------------------------------------------------------------------------------------------
                                                                                             
----------------------------------------------------------------------------------------------------------------------------------
TRINITY INDUSTRIES        COMMON     896522109      28,092   516,500 SH      SOLE                            516,500            0
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TRW AUTOMOTIVE HOLDINGS
CORP                      COMMON     87264S106       5,578   239,400 SH      SOLE                            239,400            0
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U G I CORPORATION NEW     COMMON     902681105         354    16,800 SH      SOLE                                  0       16,800
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U S BANCORP               COMMON     902973304       3,513   115,175 SH      SOLE                            115,100           75
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USG CORP                  COMMON     903293405      39,779   418,900 SH      SOLE                            418,900            0
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VALERO ENERGY CORP        COMMON     91913Y100      31,642   529,300 SH      SOLE                            529,300            0
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VERIZON COMMUNICATIONS    COMMON     92343V104      11,502   337,700 SH      SOLE                            324,275       13,425
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VODAFONE GROUP PLC         ADR       92857W100       3,292   157,525 SH      SOLE                            153,700        3,825
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WABTEC CORP               COMMON     929740108      27,078   830,600 SH      SOLE                            830,600            0
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WACHOVIA CORP             COMMON     929903102       3,682    65,700 SH      SOLE                             65,700            0
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WALTER INDUSTRIES INC     COMMON     93317Q105       9,600   144,100 SH      SOLE                            144,100            0
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WASHINGTON MUTUAL INC     COMMON     939322103       3,559    83,500 SH      SOLE                             83,500            0
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WATSCO INC                COMMON     942622200      25,137   353,800 SH      SOLE                            353,800            0
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WELLCARE HEALTH PLANS INC COMMON     94946T106      13,087   288,000 SH      SOLE                            288,000            0
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WELLS FARGO & CO          COMMON     949746101       4,509    70,590 SH      SOLE                             55,400       15,190
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WESTAMERICA BANCORP       COMMON     957090103         489     9,419 SH      SOLE                                  0        9,419
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WESTERN DIGITAL CORP      COMMON     958102105      27,424 1,411,400 SH      SOLE                          1,411,400            0
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WESTERN GAS RESOURCES INC COMMON     958259103       6,359   131,800 SH      SOLE                            131,800            0
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WEYERHAEUSER CO           COMMON     962166104       3,788    52,300 SH      SOLE                             52,300            0
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WILLIAM LYON HOMES        COMMON     552074106       4,200    43,900 SH      SOLE                             43,900            0
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WORLD AIR HOLDINGS INC    COMMON     98142V104       3,561   362,600 SH      SOLE                            362,600            0
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Page 9 of 9                                                           03/31/2006


                                                     FORM 13F INFORMATION TABLE

                                         Name of Reporting Manager: Hennessy Advisors, Inc.

                                                                                                    Column
      Column 1:         Column 2:    Column 3:   Column 4:    Column 5:              Column 6:         7:         Column 8:
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                          Title                   Market
                           of         CUSIP       Value       Shares or                              Other
    Name of Issuer        Class       Number    (x$1,000)  Principal Amount  Investment Discretion   Mgrs.    Voting Authority
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                                                                    SH/ Put/        Shared   Shared
                                                                    PRN Call  Sole  Defined   Other         Sole    Shared  None
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XL CAPITAL LTD             ADR       G98255105       3,340    52,100 SH      SOLE                             52,100            0
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                   TOTAL                         2,195,396
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