-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 VGallQP+uRyC6pg5CalK8W5G3ZAYtc0ByvDOgoP8b1v2ELWeo+jOMUPCpNwlX38O
 JMal5xh3PE4sqv9MkKM3eA==

<SEC-DOCUMENT>0001312815-05-000004.txt : 20050104
<SEC-HEADER>0001312815-05-000004.hdr.sgml : 20050104
<ACCEPTANCE-DATETIME>20050104172026
ACCESSION NUMBER:		0001312815-05-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041231
FILED AS OF DATE:		20050104
DATE AS OF CHANGE:		20050104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LOFTY CHARLES F
		CENTRAL INDEX KEY:			0001312815

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24073
		FILM NUMBER:		05508755

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		256-837-2620

	MAIL ADDRESS:	
		STREET 1:		DIGITAL FUSION, INC.
		STREET 2:		4940-A CORPORATE DRIVE
		CITY:			HUNTSVILLE
		STATE:			AL
		ZIP:			35805

	FORMER NAME:	
		FORMER CONFORMED NAME:	LOFTY CHARLES A
		DATE OF NAME CHANGE:	20041227

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DIGITAL FUSION INC/NJ/
		CENTRAL INDEX KEY:			0001057257
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER PROGRAMMING, DATA PROCESSING, ETC. [7370]
		IRS NUMBER:				133817344
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4940-A CORPORATE DRIVE
		CITY:			HUNTSVILLE
		STATE:			AL
		ZIP:			35805
		BUSINESS PHONE:		2568372620

	MAIL ADDRESS:	
		STREET 1:		4940-A CORPORATE DRIVE
		CITY:			HUNTSVILLE
		STATE:			AL
		ZIP:			35805

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IBS INTERACTIVE INC
		DATE OF NAME CHANGE:	19980306
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001057257</issuerCik>
        <issuerName>DIGITAL FUSION INC/NJ/</issuerName>
        <issuerTradingSymbol>DIGF.OB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001312815</rptOwnerCik>
            <rptOwnerName>LOFTY CHARLES F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>DIGITAL FUSION, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4940-A CORPORATE DRIVE</rptOwnerStreet2>
            <rptOwnerCity>HUNTSVILLE</rptOwnerCity>
            <rptOwnerState>AL</rptOwnerState>
            <rptOwnerZipCode>35805</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.6</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>15000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.6</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2004-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, par value $.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The options were awarded pursuant to approval by the issuer's board of directors.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Charles F Lofty</signatureName>
        <signatureDate>2005-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>

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