<SEC-DOCUMENT>0001398344-25-002901.txt : 20250214
<SEC-HEADER>0001398344-25-002901.hdr.sgml : 20250214
<ACCEPTANCE-DATETIME>20250214160523
ACCESSION NUMBER:		0001398344-25-002901
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250211
FILED AS OF DATE:		20250214
DATE AS OF CHANGE:		20250214

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GOLDSTEIN PHILLIP
		CENTRAL INDEX KEY:			0001067621
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04992
		FILM NUMBER:		25628320

	MAIL ADDRESS:	
		STREET 1:		60 HERITAGE DRIVE
		CITY:			PLEASANTVILLE
		STATE:			NY
		ZIP:			10570

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Bulldog Investors, LLP
		CENTRAL INDEX KEY:			0001504304
		ORGANIZATION NAME:           	
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04992
		FILM NUMBER:		25628321

	BUSINESS ADDRESS:	
		STREET 1:		PARK 80 WEST - PLAZA TWO
		STREET 2:		250 PEHLE AVE. SUITE 708
		CITY:			SADDLE BROOK
		STATE:			NJ
		ZIP:			07663
		BUSINESS PHONE:		201 556-0092

	MAIL ADDRESS:	
		STREET 1:		PARK 80 WEST - PLAZA TWO
		STREET 2:		250 PEHLE AVE. SUITE 708
		CITY:			SADDLE BROOK
		STATE:			NJ
		ZIP:			07663

	FORMER NAME:	
		FORMER CONFORMED NAME:	Bulldog Investors, LLC
		DATE OF NAME CHANGE:	20130610

	FORMER NAME:	
		FORMER CONFORMED NAME:	Brooklyn Capital Management LLC
		DATE OF NAME CHANGE:	20101026

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Dakos Andrew
		CENTRAL INDEX KEY:			0001341021
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04992
		FILM NUMBER:		25628319

	MAIL ADDRESS:	
		STREET 1:		250 PEHLE AVE.
		STREET 2:		SUITE 708
		CITY:			SADDLE BROOK
		STATE:			NJ
		ZIP:			07663

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MFS HIGH YIELD MUNICIPAL TRUST
		CENTRAL INDEX KEY:			0000809844
		ORGANIZATION NAME:           	
		IRS NUMBER:				042950868
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1130

	BUSINESS ADDRESS:	
		STREET 1:		111 HUNTINGTON AVENUE
		STREET 2:		24TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199
		BUSINESS PHONE:		617-954-5000

	MAIL ADDRESS:	
		STREET 1:		111 HUNTINGTON AVENUE
		STREET 2:		24TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02199

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	COLONIAL MUNICIPAL INCOME TRUST
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>fp0092342-1_3.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2025-02-11</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000809844</issuerCik>
        <issuerName>MFS HIGH YIELD MUNICIPAL TRUST</issuerName>
        <issuerTradingSymbol>CMU</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001504304</rptOwnerCik>
            <rptOwnerName>Bulldog Investors, LLP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PARK 80 WEST - PLAZA TWO</rptOwnerStreet1>
            <rptOwnerStreet2>250 PEHLE AVE. SUITE 708</rptOwnerStreet2>
            <rptOwnerCity>SADDLE BROOK</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07663</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001067621</rptOwnerCik>
            <rptOwnerName>GOLDSTEIN PHILLIP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PARK 80 WEST - PLAZA TWO</rptOwnerStreet1>
            <rptOwnerStreet2>250 PEHLE AVE. SUITE 708</rptOwnerStreet2>
            <rptOwnerCity>SADDLE BROOK</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07663</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001341021</rptOwnerCik>
            <rptOwnerName>Dakos Andrew</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PARK 80 WEST - PLAZA TWO</rptOwnerStreet1>
            <rptOwnerStreet2>250 PEHLE AVE. SUITE 708</rptOwnerStreet2>
            <rptOwnerCity>SADDLE BROOK</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07663</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares are held by Phillip Goldstein. Bulldog Investors, LLP and Andrew Dakos disclaim beneficial interest in such shares except to the extent of any pecuniary interest therein. Andrew Dakos and Phillip Goldstein are the partners of Bulldog Investors, LLP.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Bulldog Investors, LLP By: /s/ Phillip Goldstein, Partner</signatureName>
        <signatureDate>2025-02-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Phillip Goldstein</signatureName>
        <signatureDate>2025-02-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Andrew Dakos</signatureName>
        <signatureDate>2025-02-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
