As filed with the Securities and Exchange Commission on June 22, 2001
                                                     1933 Act File No. 333-58758
                                                     1940 Act File No. 811-09013
--------------------------------------------------------------------------------
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                     U.S. SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                    FORM N-2
                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933        [ ]
                          PRE-EFFECTIVE AMENDMENT NO. 2         [x]
                          POST-EFFECTIVE AMENDMENT NO.          [ ]
                                     AND/OR
                        REGISTRATION STATEMENT UNDER THE
                         INVESTMENT COMPANY ACT OF 1940         [ ]
                                 AMENDMENT NO. 5                [x]
                        (CHECK APPROPRIATE BOX OR BOXES)

                         EATON VANCE SENIOR INCOME TRUST
                         -------------------------------
               (EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)

     THE EATON VANCE BUILDING, 255 STATE STREET, BOSTON, MASSACHUSETTS 02109
     -----------------------------------------------------------------------
               (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES) (ZIP CODE)

       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (617) 482-8260
       ------------------------------------------------------------------

                                 ALAN R. DYNNER
     THE EATON VANCE BUILDING, 255 STATE STREET, BOSTON, MASSACHUSETTS 02109
     -----------------------------------------------------------------------
                     (NAME AND ADDRESS OF AGENT FOR SERVICE)


     Approximate Date of Proposed Public Offering:  As soon as practicable after
the effective date of this Registration Statement.

     If any of the securities being registered on this Form will be offered on a
delayed or continuous  basis in reliance on Rule 415 under the Securities Act of
1933, other than securities  offered in connection with a dividend  reinvestment
plan, check the following box. [ ]

It is proposed that this filing will become  effective  (check  appropriate box)
[ ] when declared effective pursuant to section 8(c)

The Registrant hereby amends this  Registration  Statement on such date or dates
as may be necessary to delay its effective date until the Registrant  shall file
a further amendment which specifically  states that this Registration  Statement
shall  thereafter  become  effective  in  accordance  with  Section  8(a) of the
Securities  Act of  1933  or  until  the  Registration  Statement  shall  become
effective on such date as the Commission,  acting pursuant to said Section 8(a),
may determine.


                         EATON VANCE SENIOR INCOME TRUST
                            AUCTION PREFERRED SHARES

                              CROSS REFERENCE SHEET
                           ITEMS REQUIRED BY FORM N-2
                           --------------------------


PART A.
ITEM NO.                  ITEM CAPTION                                                PROSPECTUS CAPTION
--------                  ------------                                                ------------------
                                                                          
1.                        Outside Front Cover                                   Front Cover Page
2.                        Inside Front and Outside Back Cover Page              Front and Back Cover Page
3.                        Fee Table and Synopsis                                Prospectus Summary
4.                        Financial Highlights                                  Financial Highlights and Investment Performance
5.                        Plan of Distribution                                  Front Cover Page; Prospectus Summary; The Auction;
                                                                                   Underwriting
6.                        Selling Shareholders                                  Not Applicable
7.                        Use of Proceeds                                       Use of Proceeds; Investment Objective, Policies and
                                                                                   Risks
8.                        General Description of the Registrant                 Organization and Management of the Trust;
                                                                                   Investment Objective, Policies and Risks;
                                                                                   Description of Capital Structure
9.                        Management                                            Management of the Trust; Shareholder Servicing
                                                                                   Agent, Custodian and Transfer Agent
10.                       Capital Stock, Long-Term Debt, and Other              Organization and Management of the Trust; Taxes;
                            Securities                                             Description of Preferred Shares
11.                       Defaults and Arrears on Senior Securities             Not Applicable
12.                       Legal Proceedings                                     Not Applicable
13.                       Table of Contents of the Statement of                 Table of Contents of the Statement of Additional
                            Additional Information                                 Information

PART B                                                                                   STATEMENT OF
ITEM NO.                  ITEM CAPTION                                          ADDITIONAL INFORMATION CAPTION
--------                  ------------                                          ------------------------------
14.                       Cover Page                                            Cover Page
15.                       Table of Contents                                     Table of Contents
16.                       General Information and History                       Not Applicable
17.                       Investment Objective and Policies                     Additional Investment Information and
                                                                                   Restrictions
18.                       Management                                            Trustees and Officers; Investment Advisory and
                                                                                   Other Services
19.                       Control Persons and Principal Holders of              Other Information
                            Securities
20                        Investment Advisory and Other Services                Investment Advisory and Other Services
21.                       Brokerage Allocation and Other Practices              Portfolio Trading
22.                       Tax Status                                            Taxes
23.                       Financial Statements                                  Financial Statements



                                       C-1

The purpose of this filing is to file exhibits to the Registration  Statement on
Form N-2. The  prospectus  and  statement of additional  information  were filed
electronically  with the Commission in a  Registration  Statement on Form N-2 on
March 13, 2000 (Accession No. 0000950156-00-000169) and amended in Pre-Effective
Amendment No. 1 filed June 19, 2001 (Accession No. 0000940394-01-500292) and are
incorporated by reference herein.









                                       C-2

                                     PART C

                                OTHER INFORMATION

ITEM 24. FINANCIAL STATEMENTS AND EXHIBITS


     (1)  FINANCIAL STATEMENTS:

          INCLUDED IN PART A:

          Financial  highlights  for the six months ended December 31, 2000, the
          year ended June 30,  2000 and the period  from the start of  business,
          October 30, 1998, to June 30, 1999

          INCLUDED IN PART B:

               INCORPORATED  BY  REFERENCE  TO THE ANNUAL  REPORT DATED JUNE 30,
               2000 (ACCESSION NO.  0000950156-00-000423) AND TO THE SEMI-ANNUAL
               REPORT    DATED     DECEMBER    31,    2000     (ACCESSION    NO.
               0000950156-01-000120),  EACH  FILED  ELECTRONICALLY  PURSUANT  TO
               SECTION 30(B)(2) OF THE INVESTMENT COMPANY ACT OF 1940.


          Financial Statements dated June 30, 2000 for EATON VANCE SENIOR INCOME
          TRUST:

               Portfolio of Investments as of June 30, 2000
               Statement of Assets and Liabilities as of June 30, 2000
               Statement of Operations for the year ended June 30, 2000
               Statements of Changes in Net Assets for the year ended June 30,
                 2000 and for the period from the start of business, October 30,
                 1998, to June 30, 1999
               Statement of Cash Flows for the year ended June 30, 2000
               Financial Highlights for the year ended June 30, 2000 and for the
                 period from the start of business, October 30, 1998, to June
                 30, 1999
               Notes to Financial Statements
               Independent Auditors' Report

          Financial  Statements  dated  December 31, 2000 for EATON VANCE SENIOR
          INCOME TRUST:
               Portfolio of Investments as of December 31, 2000
               Statement of Assets and Liabilities as of December 31, 2000
               Statement of Operations for the six months ended December 31,2000
               Statements of Changes in Net Assets for the six months ended
                 December 31, 2000 and for the year ended June 30, 2000
               Statement of Cash Flows for the six months ended December 31,2000
               Financial Highlights for the six months ended December 31, 2000,
                 the year ended June 30, 2000 and for the period from the start
                 of business, October 30, 1998, to June 30, 1999
               Notes to Financial Statements
               Independent Auditors' Report

     (2)  EXHIBITS (WITH INAPPLICABLE ITEMS DELETED):

          (a)  Agreement and Declaration of Trust dated September 23, 1998 filed
               as Exhibit (a) to the Registration Statement under the Securities
               Act of 1933 (1933 Act File No. 333-64151) and to the Registration
               Statement under the Investment Company Act of 1940 (1940 Act File
               No.  811-09013)  filed with the  Commission on September 24, 1998
               (Registration Statement) and incorporated herein by reference.

                                       C-3

     (b)(1)    Amended By-Laws filed as Exhibit (b) to  Pre-Effective  Amendment
               No. 1 to the  Registration  Statement under the Securities Act of
               1933 (1933 Act File No.  333-64151)  and  Amendment  No. 1 to the
               Registration  Statement under the Investment  Company Act of 1940
               (1940  Act File No.  811-09013)  filed  with  the  Commission  on
               October 27, 1998 ("Amendment No. 1").

        (2)    Second Amended  By-Laws filed as Exhibit (b)(2) to  Pre-Effective
               Amendment  No.  1  to  the   Registration   Statement  under  the
               Securities Act of 1933 (1933 Act File No.  811-09013)  filed with
               the  Commission  on  June  19,  2001   ("Amendment  No.  4")  and
               incorporated herein by reference.

     (d)(1)    Specimen Certificate  representing the Registrant's Common Shares
               of  Beneficial  Interest  filed as Exhibit (d) to Amendment No. 1
               and incorporated herein by reference.

        (2)    Specimen   Certificate   representing  the  Registrant's  Auction
               Preferred  Shares of Beneficial  Interest filed as Exhibit (d)(2)
               to Amendment No. 4 and incorporated herein by reference.

     (g)       Investment  Advisory  Agreement  dated  October 19, 1998 filed as
               Exhibit  (g)  to  Amendment  No.  1 and  incorporated  herein  by
               reference.

     (h)       Form of Underwriting Agreement for Auction Preferred Shares filed
               herewith.

     (i)       The Securities and Exchange Commission has granted the Registrant
               an  exemptive  order that  permits the  Registrant  to enter into
               deferred compensation arrangements with its independent Trustees.
               See in the Matter of Capital  Exchange  Fund,  Inc.,  Release No.
               IC-20671 (November 1, 1994).

     (j)(1)    Custodian  Agreement  dated October 19, 1998 filed as Exhibit (j)
               to Amendment No. 1 and incorporated herein by reference.

        (2)    Amendment to Master  Custodian  Agreement  with  Investors Bank &
               Trust  Company dated  December 21, 1998 as Exhibit  (g)(3) to the
               Registration Statement of Eaton Vance Municipals Trust (File Nos.
               33-572 and 811-4409) (Accession No.  0000950156-99-000050)  filed
               January 25, 1999 and incorporated herein by reference.

        (3)    Extension  Agreement  dated  August 31, 2000 to Master  Custodian
               Agreement  with  Investors  Bank & Trust Company filed as Exhibit
               (j)(d) to the Post-Effective Amendment No. 4 of Eaton Vance Prime
               Rate Reserves  (File Nos.  333-32268,  811-05808)  filed with the
               Commission    on    January    18,    2001     (Accession     No.
               0000940394-01-500021) and incorporated herein by reference.

        (4)    Delegation  Agreement dated December 11, 2000 with Investors Bank
               & Trust  Company  filed as Exhibit  (j)(d) to the  Post-Effective
               Amendment  No. 5 of Eaton  Vance Prime Rate  Reserves  (File Nos.
               333-32268,  811-05808) filed with the Commission on April 3, 2001
               (Accession No.  0000940394-01-500126)  and incorporated herein by
               reference herewith.

     (k)(1)    Form of Auction Agency Agreement to the Auction  Preferred Shares
               filed herewith.

        (2)    Form of Broker-Dealer  Agreement as to the  Registrant's  Auction
               Preferred Shares filed herewith.

        (3)    Form of DTC Representations Letter as to the Registrant's Auction
               Preferred Shares filed herewith.

        (4)    Transfer  Agency and Services  Agreement  dated as of October 19,
               1998 filed as Exhibit (k)(1) to Amendment No. 1 and  incorporated
               herein by reference.

        (5)    Administration  Agreement dated October 19, 1998 filed as Exhibit
               (k)(2) to Amendment No. 1 and incorporated herein by reference.

        (6)    Shareholder  Servicing  Agreement  dated as of October  19,  1998
               filed as  Exhibit  (k)(3)  to  Amendment  No. 1 and  incorporated
               herein by reference.

                                       C-4

     (l)       Opinion and Consent of Counsel filed herewith.

     (n)       Independent Auditors' Consent filed herewith.

     (p)       Letter  Agreement with Eaton Vance  Management  dated October 23,
               1998 filed as Exhibit  (p) to  Amendment  No. 1 and  incorporated
               herein by reference.

     (r)       Code  of  Ethics  adopted  by  Eaton  Vance  Corp.,  Eaton  Vance
               Management,   Boston   Management   and  Research,   Eaton  Vance
               Distributors,  Inc. and the Eaton Vance Funds effective September
               1, 2000 as revised  November  6, 2000 filed as Exhibit  (p)(1) to
               Post-Effective Amendment No. 75 of Eaton Vance Growth Trust (File
               Nos. 02-22019, 811-1241) filed December 21, 2000 and incorporated
               herein by reference.

     (s)       Power of  Attorney  dated  April 10, 2001 filed as Exhibit (s) to
               the Registration Statement under the Securities Act of 1933 (1933
               Act  File  No.  333-58758)  and to  the  Amendment  No.  3 to the
               Registration  Statement under the Investment  Company Act of 1940
               (1940 Act File No.  811-09013) filed with the commission on April
               12, 2001 (Amendment No. 3) and incorporated herein by reference.

 ITEM 25. MARKETING ARRANGEMENTS

     To be included in Purchase Agreement to be filed as Exhibit (h) hereto.

ITEM 26. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION

     The  following  table  sets forth the  approximate  expenses  incurred  and
estimated to be in connection with the offering of Registrant:

     Registration fees                                        $  27,500
     Printing                                                 $  20,000
     Accounting fees and expenses                             $   5,000
     Legal fees and expenses                                  $  75,000

          Total                                               $ 127,500
                                                              =========

ITEM 27. PERSONS CONTROLLED BY OR UNDER COMMON CONTROL

     None.

ITEM 28. NUMBER OF HOLDERS OF SECURITIES

                    (1)                                      (2)
               TITLE OF CLASS                     NUMBER OF RECORD HOLDERS
               --------------                     ------------------------
   Auction Preferred Shares of beneficial                     0
   interest, par value $.01 per share                as of June 18, 2001

   Common Shares of beneficial interest,                 35,726,793
          par value $.01 per share                   as of June 18, 2001

ITEM 29. INDEMNIFICATION

     The Registrant's  By-Laws filed in Amendment No. 1 and incorporated  herein
by  reference  contains,  and the  Purchase  Agreement  to be filed  herewith is
expected to contain,  provisions  limiting  the  liability,  and  providing  for
indemnification, of the Trustees and officers under certain circumstances.

     Registrant's  Trustees and officers are insured under a standard investment
company errors and omissions  insurance  policy covering loss incurred by reason
of negligent errors and omissions committed in their capacities as such.

                                       C-5

     Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to trustees,  officers and  controlling  persons of the
Registrant and the Adviser and any  underwriter  to the foregoing  provisions or
otherwise, the Registrant has been advised that in the opinion of the Securities
and  Exchange  Commission  such  indemnification  is  against  public  policy as
expressed  in such Act and is,  therefore,  unenforceable.  In the event  that a
claim for  indemnification  against such liabilities  (other than the payment by
the  Registrant  of  expenses  incurred  or  paid  by  a  trustee,  officer,  or
controlling person or the Registrant and the Underwriters in connection with the
successful  defense of any action,  suit or proceeding) is asserted  against the
Registrant by such trustee,  officer or controlling person or the Distributor in
connection  with the Preferred  Shares being  registered,  the Registrant  will,
unless in the opinion of its counsel the matter has been settled by  controlling
precedent,  submit to a court of appropriate  jurisdiction  the question whether
such indemnification by it is against public policy as expressed in such Act and
will be governed by the final adjudication of such issue.

ITEM 30. BUSINESS AND OTHER CONNECTIONS OF THE INVESTMENT ADVISER

     Reference  is made to: (i) the  information  set forth  under the  captions
"Management of the Fund" in the Prospectus  and  "Investment  Advisory and Other
Services" in the Statement of Additional Information; (ii) the Eaton Vance Corp.
10-K filed under the  Securities  Exchange  Act of 1934 (File No.  1-8100);  and
(iii) the Forms ADV of Eaton Vance  Management  (File No.  801-15930) filed with
the Commission, all of which are incorporated herein by reference.

ITEM 31. LOCATION OF ACCOUNTS AND RECORDS

     All applicable  accounts,  books and documents required to be maintained by
the  Registrant by Section 31(a) of the  Investment  Company Act of 1940 and the
Rules  promulgated   thereunder  are  in  the  possession  and  custody  of  the
Registrant's  custodian,  Investors Bank & Trust Company,  200 Clarendon Street,
Boston,  MA 02116,  and its transfer  agent,  PFPC,  Inc.,  4400 Computer Drive,
Westborough,  MA 01581-5120,  with the exception of certain corporate  documents
and portfolio trading documents which are in the possession and custody of Eaton
Vance Management,  The Eaton Vance Building, 255 State Street, Boston, MA 02109.
Registrant  is  informed  that all  applicable  accounts,  books  and  documents
required to be maintained by registered  investment  advisers are in the custody
and possession of Eaton Vance Management.

ITEM 32. MANAGEMENT SERVICES

     None.

ITEM 33. UNDERTAKINGS

     (1) Registrant undertakes to suspend offering of its Preferred Shares until
it  amends  its  prospectus  if (a)  subsequent  to the  effective  date  of its
Registration  Statement,  the net asset value declines more than 10 percent from
its net asset value as of the effective date of the Registration  Statement,  or
(b) the net asset value  increases to an amount greater than its net proceeds as
stated in the prospectus.

     (2) - (4) Not applicable

     (5)(a) For purpose of determining any liability under the Securities Act of
1933,  the  information  omitted from the form of prospectus  filed as part of a
registration  statement in reliance  upon Rule 430A and contained in the form of
prospectus filed by the Registrant  pursuant to Rule 497(h) under the Securities
Act of 1933, shall be deemed to be part of this Registration Statement as of the
time it was declared effective.

     (5)(b) For the purpose of  determining  any liability  under the Securities
Act of 1933,  each  post-effective  amendment that contains a form of prospectus
shall be deemed to be a new  registration  statement  relating to the securities
offered  therein,  and the  offering  of such  securities  at that time shall be
deemed to be initial bona fide offering thereof.

     (6)  Registrant  undertakes  to send by first  class  mail or  other  means
designed to ensure equally prompt delivery,  within two business days of receipt
of a written or oral request,  its Statement of Additional  Information  for the
Preferred Shares.

                                       C-6

                                     NOTICE


A copy of the Declaration of Trust of Eaton Vance Senior Income Trust is on file
with the Secretary of State of the Commonwealth of  Massachusetts  and notice is
hereby given that this  instrument is executed on behalf of the Registrant by an
officer  of the  Registrant  as an  officer  and not  individually  and that the
obligations of or arising out of this instrument are not binding upon any of the
Trustees,  officers or shareholders individually,  but are binding only upon the
assets and property of the Registrant.









                                       C-7

                                   SIGNATURES


     Pursuant  to  the  requirements  of the  Securities  Act of  1933  and  the
Investment Company Act of 1940, the Registrant has duly caused this Amendment to
the  Registration  Statement  to be  signed on its  behalf  by the  undersigned,
thereunto  duly  authorized  in the  City of  Boston,  and the  Commonwealth  of
Massachusetts, on June 21, 2001.

                                EATON VANCE SENIOR INCOME TRUST

                                By:     /s/ James B. Hawkes
                                        -----------------------------------
                                        James B. Hawkes, President


     Pursuant to the  requirements of the Securities Act of 1933, this Amendment
to the Registration  Statement has been signed below by the following persons on
June 21, 2001 in the capacities indicated.

Signature                       Title
---------                       -----

/s/ James B. Hawkes             Trustee, President and Principal
---------------------------     Executive Officer
James B. Hawkes

/s/ James L. O'Connor           Treasurer (Principal Financial and
---------------------------     Accounting Officer)
James L. O'Connor

Jessica M. Bibliowicz*          Trustee
---------------------------
Jessica M. Bibliowicz

Donald R. Dwight*               Trustee
---------------------------
Donald R. Dwight

Samuel L. Hayes, III*           Trustee
---------------------------
Samuel L. Hayes, III

Norton H. Reamer*               Trustee
---------------------------
Norton H. Reamer

Lynn A. Stout*                  Trustee
---------------------------
Lynn A. Stout

Jack L. Treynor*                Trustee
---------------------------
Jack L. Treynor

*By:  /s/ Eric G. Woodbury
      --------------------------------------
      Eric G. Woodbury (As attorney-in-fact)

                                       C-8

                                  EXHIBIT INDEX

Exhibit No.    Description
-----------    -----------

(h)            Form of Underwriting Agreement for Auction Preferred Shares

(k)(1)         Form of Auction Agency Agreement to the Auction Preferred Shares

(k)(2)         Form of Broker-Dealer  Agreement as to the  Registrant's  Auction
               Preferred Shares

(k)(3)         Form of DTC Representation  Letter as to the Registrant's Auction
               Preferred Shares

(l)            Opinion and Consent of Counsel

(n)            Independent Auditors' Consent

                                       C-9