-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 O2uRxzPKUXtzwKwn/YNXQHH5Uzpof5wkN1AAKkAdbHuTLrSMGU0EetaExXEvMhhb
 +pB/BYsm9GWGXxqaWZuqIw==

<SEC-DOCUMENT>0000074208-04-000009.txt : 20040217
<SEC-HEADER>0000074208-04-000009.hdr.sgml : 20040216
<ACCEPTANCE-DATETIME>20040217162455
ACCESSION NUMBER:		0000074208-04-000009
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20011114
FILED AS OF DATE:		20040217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WALLIS W MARK
		CENTRAL INDEX KEY:			0001195705

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10524
		FILM NUMBER:		04609119

	BUSINESS ADDRESS:	
		STREET 1:		UNITED DOMINION REALTY TRUST INC
		CITY:			HIGHLANDS RANCH
		STATE:			CO
		ZIP:			80129

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNITED DOMINION REALTY TRUST INC
		CENTRAL INDEX KEY:			0000074208
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				540857512
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		400 EAST CARY STREET
		CITY:			RICHMOND
		STATE:			VA
		ZIP:			23219-3802
		BUSINESS PHONE:		8047802691

	MAIL ADDRESS:	
		STREET 1:		400 EAST CARY STREET
		CITY:			RICHMOND
		STATE:			VA
		ZIP:			23219-3802

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	OLD DOMINION REAL ESTATE INVESTMENT TRUST
		DATE OF NAME CHANGE:	19850110

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	OLD DOMINION REIT ONE
		DATE OF NAME CHANGE:	19770921

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	OLD DOMINION REAL ESTATE INVESTMENT TRUS
		DATE OF NAME CHANGE:	19741216
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>c0001195705d20040217f4af.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2001-11-14</periodOfReport>

    <dateOfOriginalSubmission>2001-11-14</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000074208</issuerCik>
        <issuerName>UNITED DOMINION REALTY TRUST INC</issuerName>
        <issuerTradingSymbol>UDR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001195705</rptOwnerCik>
            <rptOwnerName>WALLIS W MARK</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>400 EAST CARY STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>RICHMOND</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>23219</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Executive Vice Presiden</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>38168</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2001-11-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1650</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>14.3</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1650</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>SEP IRA</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This amendment is being filed to correct the nature of the ownership.  The purchase of these shares was incorrectly reported as direct ownership and should have been reported as an indirect SEP IRA ownership.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>W. MARK WALLIS</signatureName>
        <signatureDate>2004-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
