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 811-21321
                                                           -----

Pioneer Municipal High Income Trust
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(Exact name of registrant as specified in charter)

60 State Street Boston, MA  02109
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(Address of principal executive offices)

Dorothy Bourassa
60 State Street
Boston, MA  02109
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(Name and address of agent for service)

Registrant's telephone number, including area code:  (617) 742-7825

Date of fiscal year end:  April 30

Date of reporting period:  July 1, 2003 to June 30, 2004

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)  Pioneer Municipal High Income Trust

By (Signature and Title)  /s/  John F. Cogan, Jr.
                         -------------------------
                         John F. Cogan, Jr., Chairman and President

Date  August 25, 2004
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===================== PIONEER MUNICIPAL HIGH INCOME TRUST ======================

The Fund held no securities during the period covered by this report in which
there was a securityholder vote. Accordingly, there are no proxy votes to
report.