-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 A62RihTy/jvQHpKrC+IJ6bkTN3yNVZNkWSC5k7M9f7mabw+Knv/GEEy/iu1GbiIl
 i7tRNCedBV1mB9Xr370JpQ==

<SEC-DOCUMENT>0001090084-07-000007.txt : 20070518
<SEC-HEADER>0001090084-07-000007.hdr.sgml : 20070518
<ACCEPTANCE-DATETIME>20070518105512
ACCESSION NUMBER:		0001090084-07-000007
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070517
FILED AS OF DATE:		20070518
DATE AS OF CHANGE:		20070518

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:			ROETT RIORDAN
		CENTRAL INDEX KEY:			0001090084

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-05497
		FILM NUMBER:		07863405

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		2026635728

	MAIL ADDRESS:	
		STREET 1:		JOHN HOPKINS UNIVERSITY
		STREET 2:		1740 MASSACHUSETTS AVE
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20036
</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>2007-05-17</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001090084</rptOwnerCik>
            <rptOwnerName>ROETT RIORDAN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>JOHN HOPKINS UNIVERSITY</rptOwnerStreet1>
            <rptOwnerStreet2>1740 MASSACHUSETTS AVE</rptOwnerStreet2>
            <rptOwnerCity>WASHINGTON</rptOwnerCity>
            <rptOwnerState>DC</rptOwnerState>
            <rptOwnerZipCode>20036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>William J. Renahan by Power of Attorney for Dr. Riordan Roett</signatureName>
        <signatureDate>2007-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----