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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 UKv6GGhqFnA+L61C1gItoacfQ1ztL0ubtJwT3EOGcV7YXY1AjTxedn505Dx5f0Fe
 SIkH6XxJ/XvBD+R6HBc9XA==

<SEC-DOCUMENT>0000941138-08-000003.txt : 20080122
<SEC-HEADER>0000941138-08-000003.hdr.sgml : 20080121
<ACCEPTANCE-DATETIME>20080122094211
ACCESSION NUMBER:		0000941138-08-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080118
FILED AS OF DATE:		20080122
DATE AS OF CHANGE:		20080122

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:			HANDY KENNETH
		CENTRAL INDEX KEY:			0001231018

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13739
		FILM NUMBER:		08540402

	MAIL ADDRESS:	
		STREET 1:		1 S CHURCH
		STREET 2:		STE 1820
		CITY:			TUCSON
		STATE:			AZ
		ZIP:			85701
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-01-18</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001231018</rptOwnerCik>
            <rptOwnerName>HANDY KENNETH</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1 S. CHURCH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>UE183</rptOwnerStreet2>
            <rptOwnerCity>TUCSON</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85701</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-01-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>109.76</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>30.37</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>109.76</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6499.8</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each share of phantom stock is the economic equivalent of one share of common stock.  The shares of phantom stock become payable, in cash or common stock, at the election of UniSource Energy Corporation, upon the reporting person's termination of service as a director.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>C. David Lamoreaux, Attorney in Fact</signatureName>
        <signatureDate>2008-01-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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