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                                 UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                            Washington, D.C.  20549

                                   FORM N-PX

                    ANNUAL REPORT OF PROXY VOTING RECORD OF
                   REGISTERED MANAGEMENT INVESTMENT COMPANIES

                  Investment Company Act file number 811-9537
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                         MFS CALIFORNIA MUNICIPAL FUND*
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               (Exact name of registrant as specified in charter)

               500 Boylston Street, Boston, Massachusetts  02116
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              (Address of principal executive offices) (Zip code)

                                Susan S. Newton
                    Massachusetts Financial Services Company
                              500 Boylston Street
                          Boston, Massachusetts  02116
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                    (Name and address of agents for service)

      Registrant's telephone number, including area code:  (617) 954-5000
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                      Date of fiscal year end: November 30
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             Date of reporting period: July 1, 2010 - June 30, 2011
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*  Prior to October 1, 2010, the MFS California Municipal Fund was known as
     the MFS California Insured Municipal Fund.

ITEM 1. PROXY VOTING RECORD.

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******************************* FORM N-Px REPORT *******************************

ICA File Number: 811-09537
Reporting Period: 07/01/2010 - 06/30/2011
MFS California Municipal Fund









==================== MFS CALIFORNIA MUNICIPAL FUND =====================

There is no proxy voting activity for the fund, as the fund did not hold any
votable positions during the reporting period.
========== END NPX REPORT


                                   SIGNATURES

Pursuant to the requirements of 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: MFS CALIFORNIA MUNICIPAL FUND*

By (Signature and Title):  MARIA F. DIORIODWYER*
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                           Maria F. DiOrioDwyer, Principal Executive Officer

Date: August 12, 2011

*By (Signature and Title)  /s/ Susan  S. Newton
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                           Susan S. Newton, as attorney-in-fact

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*    Executed by Susan S. Newton on behalf of Maria F. DiOrioDwyer pursuant to
     a Power of Attorney dated October 26, 2010. (1)

(1)  Incorporated by reference to MFS Series Trust XIII (File Nos. 2-74959 and
     811-3327) Post-Effective Amendment No. 45 filed with the SEC via EDGAR on
     March 10, 2011.