<SEC-DOCUMENT>0000899243-18-004389.txt : 20180216
<SEC-HEADER>0000899243-18-004389.hdr.sgml : 20180216
<ACCEPTANCE-DATETIME>20180216144620
ACCESSION NUMBER:		0000899243-18-004389
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180214
FILED AS OF DATE:		20180216
DATE AS OF CHANGE:		20180216

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			UBS Group AG
		CENTRAL INDEX KEY:			0001610520
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		STATE OF INCORPORATION:			V8
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-21321
		FILM NUMBER:		18620791

	BUSINESS ADDRESS:	
		STREET 1:		BAHNHOFSTRASSE 45
		CITY:			ZURICH
		STATE:			V8
		ZIP:			CH-8001
		BUSINESS PHONE:		41-44-234-1111

	MAIL ADDRESS:	
		STREET 1:		BAHNHOFSTRASSE 45
		CITY:			ZURICH
		STATE:			V8
		ZIP:			CH-8001

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PIONEER MUNICIPAL HIGH INCOME TRUST
		CENTRAL INDEX KEY:			0001223026
		IRS NUMBER:				030512430
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0430

	BUSINESS ADDRESS:	
		STREET 1:		60 STATE STREET
		STREET 2:		19TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02109
		BUSINESS PHONE:		6177427825
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-02-14</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001223026</issuerCik>
        <issuerName>PIONEER MUNICIPAL HIGH INCOME TRUST</issuerName>
        <issuerTradingSymbol>MHI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001610520</rptOwnerCik>
            <rptOwnerName>UBS Group AG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>BAHNHOFSTRASSE 45</rptOwnerStreet1>
            <rptOwnerStreet2>PO BOX CH-8098</rptOwnerStreet2>
            <rptOwnerCity>ZURICH</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Auction Preferred Stock</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <transactionDate>
                <value>2018-02-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>899</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>556</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By subsidiary -</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Auction Preferred Stock</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <transactionDate>
                <value>2018-02-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>556</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By subsidiary -</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This Statement is filed jointly by UBS Group AG for the benefit and on behalf of UBS Securities LLC and UBS Financial Services Inc., two wholly owned subsidiaries of UBS Group AG to which UBS Group AG has delegated portions of its performance obligations with respect to the Auction Rate Securities Rights issued by UBS Group AG to certain clients and pursuant to which the securities reported herein have been purchased from such clients.</footnote>
        <footnote id="F2">This filing reports holdings of the Series of Auction Preferred Stock identified in Item 1 of this Table I on an aggregated basis.</footnote>
        <footnote id="F3">At Par</footnote>
        <footnote id="F4">(Cusip Nos 723763207, 723763306)</footnote>
    </footnotes>

    <remarks>*The relevant APS was redeemed by the issuer</remarks>

    <ownerSignature>
        <signatureName>By: /s/ Daniel Rucker, UBS Group AG</signatureName>
        <signatureDate>2018-02-16</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>By: /s/ William Chandler, UBS Group AG</signatureName>
        <signatureDate>2018-02-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
