-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 M2/6gfd1TN1BgL2TEIyxcvhpz6sG7QeoIpwDhD1b/zHI9D0hjCnzbWXmeVngLG33
 +BNMDwQrPR0W8wOpHMqvpA==

<SEC-DOCUMENT>0001393884-07-000020.txt : 20070322
<SEC-HEADER>0001393884-07-000020.hdr.sgml : 20070322
<ACCEPTANCE-DATETIME>20070322134857
ACCESSION NUMBER:		0001393884-07-000020
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070208
FILED AS OF DATE:		20070322
DATE AS OF CHANGE:		20070322

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WESTERN ASSET MUNICIPAL HIGH INCOME FUND INC.
		CENTRAL INDEX KEY:			0000830487
		STANDARD INDUSTRIAL CLASSIFICATION:	UNKNOWN SIC - 0000 [0000]
		IRS NUMBER:				000000000
		FISCAL YEAR END:			1031

	BUSINESS ADDRESS:	
		STREET 1:		CITIGROUP ASSET MANAGEMENT
		STREET 2:		125 BROAD STREET, 10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004
		BUSINESS PHONE:		212-291-2556

	MAIL ADDRESS:	
		STREET 1:		CITIGROUP ASSET MANAGEMENT
		STREET 2:		125 BROAD STREET, 10TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MUNICIPAL HIGH INCOME FUND INC
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SPECIAL OPPORTUNITIES MUNICIPAL FUND INC
		DATE OF NAME CHANGE:	19881025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Del Guercio Rocco
		CENTRAL INDEX KEY:			0001393884

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-05497
		FILM NUMBER:		07711366

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		212-291-2506

	MAIL ADDRESS:	
		STREET 1:		LEGG MASON & CO., LLC
		STREET 2:		125 BROAD STREET
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10005
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2007-02-08</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000830487</issuerCik>
        <issuerName>WESTERN ASSET MUNICIPAL HIGH INCOME FUND INC.</issuerName>
        <issuerTradingSymbol>MHF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001393884</rptOwnerCik>
            <rptOwnerName>Del Guercio Rocco</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>LEGG MASON &amp; CO., LLC</rptOwnerStreet1>
            <rptOwnerStreet2>125 BROAD STREET</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10005</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CFO of the Adviser</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>William J. Renahan by Power of Attorney for Rocco Del Guercio</signatureName>
        <signatureDate>2007-03-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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