-----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,
 L44UB5hpGzj1okSexEUE1ATET7bU91T/LXyu1hwhZkpLHSQT/4RrvNAzZTPiSIOm
 6qWBiS9udhPDL0lRetQL1A==

<SEC-DOCUMENT>0001015680-03-000455.txt : 20031119
<SEC-HEADER>0001015680-03-000455.hdr.sgml : 20031119
<ACCEPTANCE-DATETIME>20031119165751
ACCESSION NUMBER:		0001015680-03-000455
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031119
FILED AS OF DATE:		20031119

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NUVEEN MUNICIPAL HIGH INCOME OPPORTUNITY FUND
		CENTRAL INDEX KEY:			0001266585
		STATE OF INCORPORATION:			MA

	MAIL ADDRESS:	
		STREET 1:		333 WEST WACKER DRIVE
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WELLINGTON SHELIA W
		CENTRAL INDEX KEY:			0001189636

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-21449
		FILM NUMBER:		031013467

	MAIL ADDRESS:	
		STREET 1:		333 W WACKER DRIVE
		STREET 2:		C/O NUVEEN INVESTMENTS
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>wel31.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>3</documentType>
	<periodOfReport>2003-11-19</periodOfReport>
    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001266585</issuerCik>
        <issuerName>NUVEEN MUNICIPAL HIGH INCOME OPPORTUNITY FUND</issuerName>
        <issuerTradingSymbol>NMZ</issuerTradingSymbol>
	</issuer>
	<reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001189636</rptOwnerCik>
            <rptOwnerName>WELLINGTON SHELIA W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>249 EAST 48</rptOwnerStreet1>
            <rptOwnerStreet2>APT. #16C</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
			<isDirector>1</isDirector>
			<isOfficer>0</isOfficer>
			<isTenPercentOwner>0</isTenPercentOwner>
			<isOther>0</isOther>
		</reportingOwnerRelationship>
	</reportingOwner>
	<nonDerivativeTable>
		<nonDerivativeHolding>
			<securityTitle>
				<value>Common Stock</value>
			</securityTitle>
			<postTransactionAmounts>
				<sharesOwnedFollowingTransaction>
					<value>0</value>
				</sharesOwnedFollowingTransaction>
			</postTransactionAmounts>
			<ownershipNature>
				<directOrIndirectOwnership>
					<value>D</value>
				</directOrIndirectOwnership>
				<natureOfOwnership>
					<value/>
				</natureOfOwnership>
			</ownershipNature>
		</nonDerivativeHolding>
	</nonDerivativeTable>
	<footnotes>
	</footnotes>
	<remarks>
	</remarks>
	<ownerSignature>
		<signatureName>By: Jessica R. Droeger/signed under POA</signatureName>
		<signatureDate>2003-11-19</signatureDate>
	</ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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