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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Ojk3UFLAr10d0vqjZYdZL9EPLRvGFN5roO5WNBwbbwU3Ckf6LKsMel7Nbs6MjFmh
 nZNiUEPcsvI4FvO8g0KY+g==

<SEC-DOCUMENT>0000941138-10-000044.txt : 20100311
<SEC-HEADER>0000941138-10-000044.hdr.sgml : 20100311
<ACCEPTANCE-DATETIME>20100311165551
ACCESSION NUMBER:		0000941138-10-000044
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100302
FILED AS OF DATE:		20100311
DATE AS OF CHANGE:		20100311

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNISOURCE ENERGY CORP
		CENTRAL INDEX KEY:			0000941138
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		IRS NUMBER:				860786732
		STATE OF INCORPORATION:			AZ
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE SOUTH CHURCH AVENUE
		STREET 2:		SUITE 100
		CITY:			TUCSON
		STATE:			AZ
		ZIP:			85701
		BUSINESS PHONE:		520-571-4000

	MAIL ADDRESS:	
		STREET 1:		ONE SOUTH CHURCH AVENUE, SUITE 100
		STREET 2:		P.O. BOX 711
		CITY:			TUCSON
		STATE:			AZ
		ZIP:			85702

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BONAVIA PAUL J
		CENTRAL INDEX KEY:			0001004552
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		STATE OF INCORPORATION:			VA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13739
		FILM NUMBER:		10674645

	BUSINESS ADDRESS:	
		STREET 1:		800 NICOLLETT MALL
		STREET 2:		P O BOX 26532
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55402
		BUSINESS PHONE:		6122154548

	MAIL ADDRESS:	
		STREET 1:		414 NICOLLET MALL
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55401
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-02</periodOfReport>

    <issuer>
        <issuerCik>0000941138</issuerCik>
        <issuerName>UNISOURCE ENERGY CORP</issuerName>
        <issuerTradingSymbol>UNS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001004552</rptOwnerCik>
            <rptOwnerName>BONAVIA PAUL J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1 S. CHURCH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 201</rptOwnerStreet2>
            <rptOwnerCity>TUCSON</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85701</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman, President and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>30.14</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Amy J. Welander, Attorney in Fact</signatureName>
        <signatureDate>2010-03-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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