Form N-Q

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

FORM N-Q


QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number         811-10197         

        Nuveen California Dividend Advantage Municipal Fund 2         
(Exact name of registrant as specified in charter)

Nuveen Investments
        333 West Wacker Drive, Chicago, Illinois 60606         
(Address of principal executive offices) (Zip code)


Kevin J. McCarthy—Vice President and Secretary
        333 West Wacker Drive, Chicago, Illinois 60606         
(Name and address of agent for service)

Registrant's telephone number, including area code:         312-917-7700        

Date of fiscal year end:            8/31          

Date of reporting period:         5/31/07         

Form N-Q is to be used by management investment companies, other than small business investment companies registered on Form N-5 (§§ 239.24 and 274.5 of this chapter), to file reports with the Commission, not later than 60 days after the close of the first and third fiscal quarters, pursuant to rule 30b1-5 under the Investment Company Act of 1940 (17 CFR 270.30b1-5). The Commission may use the information provided on Form N-Q in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-Q, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-Q unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to the Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

Item 1. Schedule of Investments

    Portfolio of Investments (Unaudited)             
    Nuveen California Dividend Advantage Municipal Fund 2 (NVX)             
    May 31, 2007             
Principal        Optional Call         
Amount (000)    Description (1)    Provisions (2)    Ratings (3)    Value 
    Consumer Staples – 7.1% (4.6% of Total Investments)             
$             775    California County Tobacco Securitization Agency, Tobacco Settlement Asset-Backed Bonds, Sonoma    6/15 at 100.00    BBB   $   755,191 
     County Tobacco Securitization Corporation, Series 2005, 4.250%, 6/01/21             
4,625    California County Tobacco Securitization Agency, Tobacco Settlement Asset-Backed Bonds,    6/12 at 100.00    Baa3    4,812,590 
     Stanislaus County Tobacco Funding Corporation, Series 2002A, 5.500%, 6/01/33             
13,480    Golden State Tobacco Securitization Corporation, California, Enhanced Tobacco Settlement    6/22 at 100.00    BBB    10,213,391 
     Asset-Backed Bonds, Series 2007A-2, 0.000%, 6/01/37             
18,880    Total Consumer Staples            15,781,172 
    Education and Civic Organizations – 14.6% (9.6% of Total Investments)             
2,000    California Educational Facilities Authority, Revenue Bonds, Stanford University, Series 2001Q,    6/11 at 101.00    AAA    2,098,500 
     5.250%, 12/01/32             
180    California Educational Facilities Authority, Revenue Bonds, University of Redlands, Series    10/15 at 100.00    A3    186,059 
     2005A, 5.000%, 10/01/35             
    California Educational Facilities Authority, Revenue Bonds, University of the Pacific,             
    Series 2006:             
125     5.000%, 11/01/21    11/15 at 100.00    A2    130,805 
165     5.000%, 11/01/25    11/15 at 100.00    A2    171,600 
6,375    California Educational Facilities Authority, Student Loan Revenue Bonds, Cal Loan Program,    3/08 at 102.00    Aaa    6,551,078 
     Series 2001A, 5.400%, 3/01/21 – MBIA Insured (Alternative Minimum Tax)             
    California State Public Works Board, Lease Revenue Bonds, University of California, UCLA             
    Replacement Hospital Project, Series 2002A:             
7,880     5.375%, 10/01/16 – FSA Insured    10/12 at 100.00    AAA    8,466,587 
10,570     5.375%, 10/01/18 – FSA Insured    10/12 at 100.00    AAA    11,258,635 
620    California Statewide Community Development Authority, Revenue Bonds, Notre Dame de Namur    10/13 at 100.00    N/R    674,988 
     University, Series 2003, 6.500%, 10/01/23             
3,000    Long Beach Bond Financing Authority, California, Lease Revenue Refunding Bonds, Long Beach    11/11 at 101.00    AAA    3,147,390 
     Aquarium of the South Pacific, Series 2001, 5.250%, 11/01/30 – AMBAC Insured             
30,915    Total Education and Civic Organizations            32,685,642 
    Health Care – 15.2% (10.0% of Total Investments)             
2,000    California Health Facilities Financing Authority, Revenue Bonds, Casa Colina Inc., Series    4/12 at 100.00    BBB+    2,115,980 
     2001, 6.000%, 4/01/22             
1,240    California Health Facilities Financing Authority, Revenue Bonds, Cedars-Sinai Medical Center,    11/15 at 100.00    A2    1,261,353 
     Series 2005, 5.000%, 11/15/34             
7,180    California Health Facilities Financing Authority, Revenue Bonds, Sutter Health, Series 2007A,    11/16 at 100.00    AA–    7,506,977 
     5.250%, 11/15/46             
500    California Infrastructure Economic Development Bank, Revenue Bonds, Kaiser Hospital Assistance    8/11 at 102.00    A+    526,315 
     LLC, Series 2001A, 5.550%, 8/01/31             
955    California State Public Works Board, Revenue Bonds, University of California – Davis Medical    11/14 at 100.00    AAA    1,001,671 
     Center, Series 2004II-A, 5.000%, 11/01/22 – MBIA Insured             
960    California Statewide Communities Development Authority, Revenue Bonds, ValleyCare Health    7/17 at 100.00    N/R    961,450 
     System, Series 2007A, 5.125%, 7/15/31             
2,185    California Statewide Community Development Authority, Health Facility Revenue Refunding Bonds,    No Opt. Call    A+    2,356,697 
     Memorial Health Services, Series 2003A, 6.000%, 10/01/11             
2,500    California Statewide Community Development Authority, Hospital Revenue Bonds, Monterey    6/13 at 100.00    AAA    2,659,900 
     Peninsula Hospital, Series 2003B, 5.250%, 6/01/18 – FSA Insured             
6,190    California Statewide Community Development Authority, Revenue Bonds, Kaiser Permanante System,    3/16 at 100.00    A+    6,263,909 
     Series 2006, 5.000%, 3/01/41             
1,925    California Statewide Community Development Authority, Revenue Bonds, Kaiser Permanente System,    8/16 at 100.00    A+    2,005,908 
     Series 2001C, 5.250%, 8/01/31             
5,355    California Statewide Community Development Authority, Revenue Bonds, Kaiser Permanente System,    No Opt. Call    A+    5,440,252 
     Series 2002E, 4.700%, 11/01/36 (Mandatory put 6/01/09)             
2,000    California Statewide Community Development Authority, Revenue Bonds, Kaiser Permanente System,    4/17 at 100.00    A+    1,949,020 
     Series 2007A, 4.750%, 4/01/33             
32,990    Total Health Care            34,049,432 
    Housing/Multifamily – 10.0% (6.6% of Total Investments)             
2,450    ABAG Finance Authority for Non-Profit Corporations, California, Multifamily Housing Revenue    No Opt. Call    BBB    2,510,589 
     Refunding Bonds, United Dominion/2000 Post Apartments, Series 2000B, 6.250%, 8/15/30             
     (Mandatory put 8/15/08)             
3,430    California Statewide Community Development Authority, GNMA Collateralized Housing Revenue    8/12 at 105.00    Aaa    3,818,859 
     Refunding Bonds, Crowne Pointe Project, Series 2002F, 6.750%, 8/20/37             
5,962    California Statewide Community Development Authority, Multifamily Housing Revenue Refunding    6/11 at 102.00    AAA    6,304,159 
     Bonds, Claremont Village Apartments, Series 2001D, 5.500%, 6/01/31 (Mandatory put 6/01/16)             
     (Alternative Minimum Tax)             
4,000    Daly City Housing Development Finance Agency, California, Mobile Home Park Revenue Bonds,    12/13 at 102.00    A–    4,385,400 
     Franciscan Mobile Home Park Project, Series 2002A, 5.850%, 12/15/32             
205    Independent Cities Lease Finance Authority, California, Mobile Home Park Revenue Bonds, San    5/16 at 100.00    N/R    210,875 
     Juan Mobile Estates, Series 2006B, 5.850%, 5/15/41             
1,055    Rohnert Park Finance Authority, California, Senior Lien Revenue Bonds, Rancho Feliz Mobile    9/13 at 100.00    A+    1,126,160 
     Home Park, Series 2003A, 5.750%, 9/15/38             
700    Rohnert Park Finance Authority, California, Subordinate Lien Revenue Bonds, Rancho Feliz    9/13 at 100.00    N/R    749,952 
     Mobile Home Park, Series 2003B, 6.625%, 9/15/38             
3,045    Yucaipa Redevelopment Agency, California, Mobile Home Park Revenue Bonds, Rancho del Sol and    5/11 at 102.00    N/R    3,363,355 
     Grandview, Series 2001A, 6.750%, 5/15/36             
20,847    Total Housing/Multifamily            22,469,349 
    Housing/Single Family – 0.5% (0.3% of Total Investments)             
525    California Housing Finance Agency, Home Mortgage Revenue Bonds, Series 2006H, 5.750%,    2/16 at 100.00    AAA    557,996 
     8/01/30 – FGIC Insured (Alternative Minimum Tax)             
575    California Rural Home Mortgage Finance Authority, Mortgage-Backed Securities Program Single    6/11 at 102.00    AAA    583,079 
     Family Mortgage Revenue Bonds, Series 2001A, 5.650%, 12/01/31 (Alternative Minimum Tax)             
1,100    Total Housing/Single Family            1,141,075 
    Industrials – 0.6% (0.4% of Total Investments)             
1,250    California Pollution Control Financing Authority, Solid Waste Disposal Revenue Bonds, Waste    1/16 at 102.00    BBB    1,271,025 
     Management Inc., Series 2002A, 5.000%, 1/01/22 (Alternative Minimum Tax)             
    Long-Term Care – 0.7% (0.5% of Total Investments)             
1,550    California Health Facilities Financing Authority, Cal-Mortgage Insured Revenue Bonds, Northern    1/13 at 100.00    A+    1,598,453 
     California Retired Officers Community Corporation – Paradise Valley Estates, Series 2002,             
     5.125%, 1/01/22             
    Tax Obligation/General – 14.7% (9.6% of Total Investments)             
5,260    California State, General Obligation Bonds, Series 2006CD, RITES 1502, 5.680%, 12/01/32    12/15 at 100.00    AA–    4,654,995 
     (Alternative Minimum Tax) (IF)             
3,615    Colton Joint Unified School District, San Bernardino County, California, General Obligation    8/12 at 102.00    AAA    3,929,867 
     Bonds, Series 2002A, 5.500%, 8/01/22 – FGIC Insured             
    Contra Costa County Community College District, California, General Obligation Bonds,             
    Series 2002:             
3,005     5.000%, 8/01/21 – FGIC Insured    8/12 at 100.00    AAA    3,145,995 
3,300     5.000%, 8/01/22 – FGIC Insured    8/12 at 100.00    AAA    3,435,300 
1,325    Golden West Schools Financing Authority, California, General Obligation Revenue Refunding    No Opt. Call    AAA    1,528,653 
     Bonds, School District Program, Series 1998A, 6.650%, 8/01/13 – MBIA Insured             
2,500    Hemet Unified School District, Riverside County, California, General Obligation Bonds, Series    8/15 at 100.00    AAA    2,355,625 
     2007, 4.250%, 8/01/32 – FSA Insured             
3,910    Los Angeles Unified School District, California, General Obligation Bonds, Series 2006B,    7/16 at 100.00    AAA    4,039,538 
     4.750%, 7/01/24 – FGIC Insured (UB)             
2,000    Puerto Rico, General Obligation and Public Improvement Bonds, Series 2001A, 5.500%, 7/01/20 –    No Opt. Call    AAA    2,271,480 
     MBIA Insured             
355    Roseville Joint Union High School District, Placer County, California, General Obligation    8/15 at 100.00    AAA    373,314 
     Bonds, Series 2006B, 5.000%, 8/01/27 – FGIC Insured             
2,811    San Diego Unified School District, San Diego County, California, General Obligation Bonds,    7/16 at 101.00    AAA    2,805,069 
     Series 2006F-1, 4.500%, 7/01/29 – FSA Insured (UB)             
4,050    Santa Rosa High School District, Sonoma County, California, General Obligation Bonds, Series    5/11 at 101.00    AAA    4,265,055 
     2001, 5.300%, 5/01/26 – FGIC Insured             
32,131    Total Tax Obligation/General            32,804,891 
    Tax Obligation/Limited – 22.3% (14.7% of Total Investments)             
    Beaumont Financing Authority, California, Local Agency Revenue Bonds, Series 2004D:             
650     5.500%, 9/01/24    9/14 at 102.00    N/R    680,401 
385     5.800%, 9/01/35    9/14 at 102.00    N/R    409,166 
4,900    California State Public Works Board, Lease Revenue Bonds, Department of Corrections, Series    12/13 at 100.00    A    5,333,699 
     2003C, 5.500%, 6/01/16             
2,105    California, Economic Recovery Revenue Bonds, Series 2004A, 5.000%, 7/01/15    7/14 at 100.00    AA+    2,245,025 
1,200    Capistrano Unified School District, Orange County, California, Special Tax Bonds, Community    9/13 at 100.00    N/R    1,267,908 
     Facilities District 90-2 – Talega, Series 2003, 6.000%, 9/01/33             
435    Capistrano Unified School District, Orange County, California, Special Tax Bonds, Community    9/15 at 100.00    AAA    457,629 
     Facilities District, Series 2005, 5.000%, 9/01/24 – FGIC Insured             
1,330    Chino Redevelopment Agency, California, Merged Chino Redevelopment Project Area Tax Allocation    9/16 at 101.00    AAA    1,399,107 
     Bonds, Series 2006, 5.000%, 9/01/38 – AMBAC Insured (UB)             
1,500    Coachella Valley Unified School District, Riverside County, California, Certificates of    9/16 at 100.00    Aaa    1,565,955 
     Participation, Series 2007, 5.000%, 9/01/36 – AMBAC Insured             
4,845    Encinitas Public Financing Authority, California, Lease Revenue Bonds, Acquisition Project,    4/08 at 102.00    AAA    4,987,734 
     Series 2001A, 5.250%, 4/01/31 – MBIA Insured             
750    Fontana, California, Special Tax Bonds, Sierra Community Facilities District 22, Series 2004,    9/14 at 100.00    N/R    795,308 
     6.000%, 9/01/34             
1,785    Hawthorne Community Redevelopment Agency, California, Project Area 2 Tax Allocation Bonds,    9/16 at 100.00    AAA    1,908,254 
     Series 2006, 5.250%, 9/01/36 – XLCA Insured             
    Irvine, California, Unified School District, Community Facilities District Special Tax Bonds,             
    Series 2006A:             
215     5.000%, 9/01/26    9/16 at 100.00    N/R    215,854 
495     5.125%, 9/01/36    9/16 at 100.00    N/R    500,410 
2,000    Lake Elsinore Public Finance Authority, California, Local Agency Revenue Refunding Bonds,    10/13 at 102.00    N/R    2,159,780 
     Series 2003H, 6.000%, 10/01/20             
415    Lammersville School District, San Joaquin County, California, Community Facilities District    9/16 at 100.00    N/R    418,312 
     2002, Mountain House Special Tax Bonds, Series 2006, 5.125%, 9/01/35             
1,265    Lee Lake Water District, Riverside County, California, Special Tax Bonds, Community Facilities    9/13 at 102.00    N/R    1,395,371 
     District 1 of Sycamore Creek, Series 2003, 6.500%, 9/01/24             
800    Los Angeles Community Redevelopment Agency, California, Lease Revenue Bonds, Manchester Social    9/15 at 100.00    Aaa    831,448 
     Services Project, Series 2005, 5.000%, 9/01/37 – AMBAC Insured             
8,000    Los Angeles County Metropolitan Transportation Authority, California, Proposition C Second    7/08 at 101.00    AAA    8,158,160 
     Senior Lien Sales Tax Revenue Refunding Bonds, Series 1998A, 5.000%, 7/01/23 – AMBAC Insured             
500    North Natomas Community Facilities District 4, Sacramento, California, Special Tax Bonds,    9/14 at 102.00    N/R    501,615 
     Series 2006D, 5.000%, 9/01/33             
2,000    Orange County, California, Special Tax Bonds, Community Facilities District 02-1 of Ladera    8/11 at 101.00    N/R    2,091,540 
     Ranch, Series 2003A, 5.550%, 8/15/33             
2,500    Petaluma Community Development Commission, California, Tax Allocation Bonds, Merged Project    5/17 at 100.00    AAA    2,442,325 
     Area, Series 2007, 4.500%, 5/01/39 – AMBAC Insured             
2,000    Puerto Rico Public Finance Corporation, Commonwealth Appropriation Bonds, Series 2002E,    No Opt. Call    BBB–    2,341,300 
     6.000%, 8/01/26             
385    Rialto Redevelopment Agency, California, Tax Allocation Bonds, Merged Project Area, Series    9/15 at 100.00    AAA    399,865 
     2005A, 5.000%, 9/01/35 – XLCA Insured             
475    Roseville, California, Certificates of Participation, Public Facilities, Series 2003A, 5.000%,    8/13 at 100.00    AAA    493,207 
     8/01/25 – AMBAC Insured             
700    Sacramento, California, Special Tax Bonds, North Natomas Community Facilities District 4,    9/14 at 100.00    N/R    742,721 
     Series 2003C, 6.000%, 9/01/33             
970    San Marcos Public Facilities Authority, California, Special Tax Bonds, Community Facilities    9/09 at 102.00    N/R    1,010,944 
     District 99-1, Series 2003B, 6.000%, 9/01/24             
1,530    San Marcos Public Facilities Authority, California, Tax Allocation Bonds, Project Areas 2 and    8/15 at 100.00    AAA    1,591,781 
     3, Series 2005C, 5.000%, 8/01/35 – AMBAC Insured             
1,930    West Patterson Financing Authority, California, Special Tax Bonds, Community Facilities    9/13 at 103.00    N/R    2,165,055 
     District 01-1, Series 2003B, 6.750%, 9/01/30             
500    West Patterson Financing Authority, California, Special Tax Bonds, Community Facilities    9/13 at 102.00    N/R    532,895 
     District 01-1, Series 2004B, 6.000%, 9/01/39             
850    West Patterson Financing Authority, California, Special Tax Bonds, Community Facilities    9/13 at 103.00    N/R    919,437 
     District 2001-1, Series 2004A, 6.125%, 9/01/39             
47,415    Total Tax Obligation/Limited            49,962,206 
    Transportation – 10.2% (6.7% of Total Investments)             
1,930    Bay Area Toll Authority, California, Revenue Bonds, San Francisco Bay Area Toll Bridge, Series    4/16 at 100.00    AA    2,026,133 
     2006, 5.000%, 4/01/31             
7,000    Foothill/Eastern Transportation Corridor Agency, California, Toll Road Revenue Refunding    1/14 at 101.00    BBB–    6,522,670 
     Bonds, Series 1999, 0.000%, 1/15/27             
5,585    Port of Oakland, California, Revenue Bonds, Series 2002N, 5.000%, 11/01/16 – MBIA Insured    11/12 at 100.00    AAA    5,795,164 
     (Alternative Minimum Tax) (4)             
    San Francisco Airports Commission, California, Revenue Bonds, San Francisco International             
    Airport, Second Series 2003, Issue 29A:             
2,430     5.250%, 5/01/18 – FGIC Insured (Alternative Minimum Tax)    5/13 at 100.00    AAA    2,553,274 
2,555     5.250%, 5/01/19 – FGIC Insured (Alternative Minimum Tax)    5/13 at 100.00    AAA    2,679,147 
1,000    San Francisco Airports Commission, California, Revenue Bonds, San Francisco International    5/13 at 100.00    AAA    1,058,070 
     Airport, Second Series 2003, Issue 29B, 5.125%, 5/01/17 – FGIC Insured             
2,000    San Francisco Airports Commission, California, Revenue Refunding Bonds, San Francisco    5/12 at 100.00    AAA    2,090,540 
     International Airport, Second Series 2002, Issue 28A, 5.250%, 5/01/17 – MBIA Insured             
     (Alternative Minimum Tax)             
22,500    Total Transportation            22,724,998 
    U.S. Guaranteed – 36.5% (23.9% of Total Investments) (5)             
9,000    Anitoch Area Public Facilities Financing Agency, California, Special Tax Bonds, Community    8/11 at 100.00    AAA    9,516,510 
     Facilities District 1989-1, Series 2001, 5.250%, 8/01/25 (Pre-refunded 8/01/11) – MBIA Insured             
6,000    California Department of Water Resources, Power Supply Revenue Bonds, Series 2002A, 5.125%,    5/12 at 101.00    Aaa    6,410,100 
     5/01/18 (Pre-refunded 5/01/12)             
1,000    California, General Obligation Bonds, Series 2004, 5.125%, 2/01/27 (Pre-refunded 2/01/14)    2/14 at 100.00    A+ (5)    1,073,980 
3,000    Central California Joint Powers Health Finance Authority, Certificates of Participation,    2/10 at 101.00    AAA    3,186,930 
     Community Hospitals of Central California Obligated Group, Series 2000, 6.000%, 2/01/30             
     (Pre-refunded 2/01/10)             
3,200    Golden State Tobacco Securitization Corporation, California, Tobacco Settlement Asset-Backed    6/13 at 100.00    AAA    3,506,560 
     Bonds, Series 2003A-1, 6.250%, 6/01/33 (Pre-refunded 6/01/13)             
1,195    Lincoln, California, Special Tax Bonds, Lincoln Crossing Community Facilities District 03-1,    9/13 at 102.00    N/R (5)    1,374,107 
     Series 2003A, 6.500%, 9/01/25 (Pre-refunded 9/01/13)             
905    Lincoln, California, Special Tax Bonds, Lincoln Crossing Community Facilities District 03-1,    9/13 at 102.00    N/R (5)    1,015,872 
     Series 2004, 6.000%, 9/01/34 (Pre-refunded 9/01/13)             
7,530    Los Angeles Unified School District, California, General Obligation Bonds, Series 2000D,    7/10 at 100.00    AAA    7,890,762 
     5.375%, 7/01/25 (Pre-refunded 7/01/10) – FGIC Insured             
10,840    Los Angeles Unified School District, California, General Obligation Bonds, Series 2002E,    7/12 at 100.00    AAA    11,448,665 
     5.000%, 7/01/19 (Pre-refunded 7/01/12) – MBIA Insured             
1,250    Los Angeles Unified School District, California, General Obligation Bonds, Series 2003A,    7/13 at 100.00    AAA    1,347,225 
     5.250%, 7/01/20 (Pre-refunded 7/01/13) – FSA Insured             
3,000    Northern California Tobacco Securitization Authority, Tobacco Settlement Asset-Backed Bonds,    6/11 at 100.00    AAA    3,175,530 
     Series 2001A, 5.375%, 6/01/41 (Pre-refunded 6/01/11)             
6,000    Riverside County Redevelopment Agency, California, Tax Allocation Bonds, Jurupa Valley Project    10/11 at 102.00    AAA    6,457,440 
     Area, Series 2001, 5.250%, 10/01/35 (Pre-refunded 10/01/11) – AMBAC Insured             
12,090    Santa Clara Valley Transportation Authority, California, Sales Tax Revenue Bonds, Series    6/11 at 100.00    AAA    12,648,795 
     2001A, 5.000%, 6/01/25 (Pre-refunded 6/01/11) – MBIA Insured (4)             
1,160    Saugus Union School District, Los Angeles County, California, General Obligation Bonds, Series    8/12 at 100.00    AAA    1,226,074 
     2002A, 5.000%, 8/01/21 (Pre-refunded 8/01/12) – FGIC Insured             
6,200    Southwestern Community College District, San Diego County, California, General Obligation    8/11 at 101.00    AAA    6,638,588 
     Bonds, Series 2001, 5.375%, 8/01/25 (Pre-refunded 8/01/11) – AMBAC Insured             
2,800    Tobacco Securitization Authority of Southern California, Tobacco Settlement Asset-Backed    6/12 at 100.00    AAA    3,008,964 
     Bonds, San Diego County Tobacco Asset Securitization Corporation, Senior Series 2001A, 5.500%,             
     6/01/36 (Pre-refunded 6/01/12)             
1,500    Whittier, California, Health Facility Revenue Bonds, Presbyterian Intercommunity Hospital,    6/12 at 101.00    A+ (5)    1,633,260 
     Series 2002, 5.600%, 6/01/22 (Pre-refunded 6/01/12)             
76,670    Total U.S. Guaranteed            81,559,362 
    Utilities – 4.8% (3.1% of Total Investments)             
5,000    Anaheim Public Finance Authority, California, Second Lien Electric Distribution Revenue Bonds,    10/14 at 100.00    AAA    5,352,550 
     Series 2004, 5.250%, 10/01/21 – MBIA Insured             
    Los Angeles Department of Water and Power, California, Power System Revenue Bonds,             
    Series 2003A-2:             
750     5.000%, 7/01/21 – MBIA Insured    7/13 at 100.00    AAA    787,020 
1,000     5.000%, 7/01/23 – MBIA Insured    7/13 at 100.00    AAA    1,044,160 
500    Los Angeles Department of Water and Power, California, Power System Revenue Bonds, Series    7/15 at 100.00    AAA    524,190 
     2005A-1, 5.000%, 7/01/31 – FSA Insured             
790    Merced Irrigation District, California, Electric System Revenue Bonds, Series 2005, 5.125%,    9/15 at 100.00    AAA    830,606 
     9/01/31 – XLCA Insured             
2,000    Santa Clara, California, Subordinate Electric Revenue Bonds, Series 2003A, 5.250%, 7/01/20 –    7/13 at 100.00    AAA    2,130,960 
     MBIA Insured             
10,040    Total Utilities            10,669,486 
    Water and Sewer – 15.3% (10.0% of Total Investments)             
4,900    East Bay Municipal Utility District, Alameda and Contra Costa Counties, California, Water    6/11 at 100.00    AAA    5,050,234 
     System Subordinated Revenue Bonds, Series 2001, 5.000%, 6/01/26 – MBIA Insured             
2,655    El Dorado Irrigation District, California, Water and Sewer Certificates of Participation,    3/14 at 100.00    AAA    2,782,520 
     Series 2004A, 5.000%, 3/01/20 – FGIC Insured             
545    Healdsburg Public Financing Authority, California, Wastewater Revenue Bonds, Series 2006,    4/16 at 100.00    AAA    569,705 
     5.000%, 4/01/36 – MBIA Insured             
3,365    Hollister Joint Powers Financing Authority, California, Wastewater Revenue Bonds, Series 2006,    6/16 at 100.00    AAA    3,509,897 
     5.000%, 6/01/37 – FSA Insured             
1,800    Pomona Public Finance Authority, California, Revenue Bonds, Water Facilities Project, Series    5/17 at 100.00    AAA    1,886,706 
     2007AY, 5.000%, 5/01/37 – AMBAC Insured             
750    Sacramento County Sanitation District Financing Authority, California, Revenue Bonds, Series    6/16 at 100.00    AAA    790,845 
     2006, 5.000%, 12/01/31 – FGIC Insured             
1,700    San Buenaventura, California, Wastewater Revenue Certificates of Participation, Series 2004,    3/14 at 100.00    AAA    1,771,502 
     5.000%, 3/01/24 – MBIA Insured             
6,885    San Diego Public Facilities Financing Authority, California, Subordinate Lien Water Revenue    8/12 at 100.00    AAA    7,208,044 
     Bonds, Series 2002, 5.000%, 8/01/21 – MBIA Insured             
10,000    San Francisco City and County Public Utilities Commission, California, Clean Water Revenue    4/13 at 100.00    AAA    10,641,399 
     Refunding Bonds, Series 2003A, 5.250%, 10/01/20 – MBIA Insured             
32,600    Total Water and Sewer            34,210,852 
$      328,888    Total Investments (cost $327,642,059) – 152.5%            340,927,943 
    Floating Rate Obligations – (2.4)%            (5,363,000) 
    Other Assets Less Liabilities – (0.9)%            (1,949,007) 
    Preferred Shares, at Liquidation Value – (49.2)%            (110,000,000) 
    Net Assets Applicable to Common Shares – 100%           $   223,615,936 

Forward Swaps outstanding at May 31, 2007:                         
        Fund            Fixed Rate            Unrealized 
    Notional    Pay/Receive    Floating Rate    Fixed Rate    Payment    Effective    Termination    Appreciation 
Counterparty    Amount    Floating Rate    Index    (Annualized)    Frequency    Date (6)    Date    (Depreciation) 
Goldman Sachs    $38,500,000    Receive    3-Month USD-LIBOR    5.681%    Semi-Annually    7/27/07    7/27/12    $(552,368) 
JPMorgan    12,000,000    Receive    3-Month USD-LIBOR    5.716       Semi-Annually    7/27/07    7/27/14    (221,433) 
Morgan Stanley    13,700,000    Pay    3-Month USD-LIBOR    5.811       Semi-Annually    7/27/07    7/27/24    345,718 
Morgan Stanley    18,500,000    Pay    3-Month USD-LIBOR    5.816       Semi-Annually    7/27/07    7/27/29    480,840 
                                $ 52,757 
USD-LIBOR (United States Dollar-London Inter-Bank Offered Rate)                     

    The Fund may invest in “zero coupon” securities. A zero coupon security does not pay a regular interest 
    coupon to its holders during the life of the security. Tax-exempt income to the holder of the security 
    comes from accretion of the difference between the original purchase price of the security at issuance 
    and the par value of the security at maturity and is effectively paid at maturity. Such securities are 
    included in the portfolio with a 0.00% coupon rate in their description. The market prices of zero coupon 
    securities generally are more volatile than the market prices of securities that pay interest periodically. 
(1)    All percentages shown in the Portfolio of Investments are based on net assets applicable to Common shares 
    unless otherwise noted. 
(2)    Optional Call Provisions: Dates (month and year) and prices of the earliest optional call or redemption. 
    There may be other call provisions at varying prices at later dates. Certain mortgage-backed securities 
    may be subject to periodic principal paydowns. 
(3)    Ratings: Using the higher of Standard & Poor’s or Moody’s rating. Ratings below BBB by Standard & Poor’s 
    Group or Baa by Moody’s Investor Service, Inc. are considered to be below investment grade. 
(4)    Portion of the investment, with an aggregate market value of $1,903,330, has been pledged to 
    collateralize the net payment obligations under forward swap contracts. 
(5)    Backed by an escrow or trust containing sufficient U.S. Government or U.S. Government agency securities 
    which ensure the timely payment of principal and interest. Such investments are normally considered to 
    be equivalent to AAA rated securities. 
(6)    Effective date represents the date on which both the Fund and counterparty commence interest payment 
    accruals on each forward swap contract. 
N/R    Not rated. 
(IF)    Inverse floating rate investment. 
(UB)    Underlying bond of an inverse floating rate trust reflected as a financing transaction pursuant to the 
    provisions of SFAS No. 140. 

Income Tax Information

The following information is presented on an income tax basis. Differences between amounts for financial statement and federal income tax purposes are primarily due to the treatment of paydown gains and losses, timing differences in recognizing taxable market discount, timing differences in recognizing certain gains and losses on investment transactions and the treatment of investments in inverse floating rate transactions subject to SFAS No. 140.

At May 31, 2007, the cost of investments was $322,265,451.

Gross unrealized appreciation and gross unrealized depreciation of investments at May 31, 2007, were as follows:

Gross unrealized:     
  Appreciation    $13,734,434 
  Depreciation    (434,734) 
Net unrealized appreciation (depreciation) of investments    $13,299,700 

Item 2. Controls and Procedures.

  1. The registrant's principal executive and principal financial officers, or persons performing similar functions, have concluded that the registrant's disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the "1940 Act") (17 CFR 270.30a-3(c))) are effective, as of a date within 90 days of the filing date of this report that includes the disclosure required by this paragraph, based on their evaluation of the controls and procedures required by Rule 30a-3(b) under the 1940 Act (17 CFR 270.30a-3(b)) and Rule 13a-15(b) or 15d-15(b) under the Securities Exchange Act of 1934 (17 CFR 240.13a-15(b) or 240.15d-15(b)).
  2. There were no changes in the registrant's internal control over financial reporting (as defined in Rule 30a-3(d) under the 1940 Act (17 CFR 270.30a-3(d)) that occurred during the registrant's last fiscal quarter that have materially affected, or are reasonably likely to materially affect, the registrant's internal control over financial reporting.

Item 3. Exhibits.

File as exhibits as part of this Form a separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the 1940 Act (17 CFR 270.30a-2(a)), exactly as set forth below: EX-99 CERT Attached hereto.


SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

(Registrant)         Nuveen California Dividend Advantage Municipal Fund 2        

By (Signature and Title)*          /s/ Kevin J. McCarthy                    
                                                    Kevin J. McCarthy
                                                    Vice President and Secretary

Date         July 27, 2007        

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By (Signature and Title)*         /s/ Gifford R. Zimmerman                    
                                                   Gifford R. Zimmerman
                                                   Chief Administrative Officer (principal executive officer) 

Date         July 27, 2007        

By (Signature and Title)*         /s/ Stephen D. Foy                              
                                                   Stephen D. Foy
                                                   Vice President and Controller (principal financial officer) 

Date        July 27, 2007        

* Print the name and title of each signing officer under his or her signature.