UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549

                                    FORM N-PX

          ANNUAL REPORT OF PROXY VOTING RECORD OF REGISTERED MANAGEMENT
                               INVESTMENT COMPANY


Investment Company Act file number         811-04025
                                   ---------------------------------------------


                        AMERICAN CENTURY MUNICIPAL TRUST
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               (Exact name of registrant as specified in charter)


   4500 MAIN STREET, KANSAS CITY, MISSOURI                             64111
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   (Address of principal executive offices)                         (Zip code)


     CHARLES A. ETHERINGTON, 4500 MAIN STREET, KANSAS CITY, MISSOURI 64111
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                     (Name and address of agent for service)


Registrant's telephone number, including area code:   816-531-5575
                                                    ----------------------------

Date of fiscal year end:     5/31
                           -------------------------

Date of reporting period:    07/01/2008 - 06/30/2009
                           -------------------------


Item 1.  Proxy Voting Record.


============================== NEW YORK TAX-FREE ===============================


There  were no  matters  relating  to a  portfolio  security  considered  at any
shareholder  meetings held during the reporting period and with respect to which
the registrant was entitled to vote.



============================= HIGH-YIELD MUNICIPAL =============================


There  were no  matters  relating  to a  portfolio  security  considered  at any
shareholder  meetings held during the reporting period and with respect to which
the registrant was entitled to vote.



============================== LONG-TERM TAX-FREE ==============================


There  were no  matters  relating  to a  portfolio  security  considered  at any
shareholder  meetings held during the reporting period and with respect to which
the registrant was entitled to vote.



================================ TAX-FREE BOND =================================


MOHAVE CNTY ARIZ INDL DEV AUTH

Ticker:                      Security ID:  60805XAK4
Meeting Date: AUG 26, 2008   Meeting Type: Written Consent
Record Date:  AUG 6, 2008

#     Proposal                                Mgt Rec   Vote Cast    Sponsor
1     The Amendments Described in the         None      Against      Management
      Material


============================ TAX-FREE MONEY MARKET =============================


There  were no  matters  relating  to a  portfolio  security  considered  at any
shareholder  meetings held during the reporting period and with respect to which
the registrant was entitled to vote.




                                   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)    AMERICAN CENTURY MUNICIPAL TRUST
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By (Signature and Title)     /s/ Jonathan S. Thomas
                         -------------------------------------------------------
                             Jonathan S. Thomas
                             President

Date   August 26, 2009
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