-----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,
 CClMJ41pp2mFUVPGKZWC3HHkxWtS/nbZshHhfSXZsQlV1QusbEYERgdHNuiiJjmm
 Cs+XarEL2pm7ZAZXm7yTRw==

<SEC-DOCUMENT>0001294441-05-000010.txt : 20050504
<SEC-HEADER>0001294441-05-000010.hdr.sgml : 20050504
<ACCEPTANCE-DATETIME>20050504155058
ACCESSION NUMBER:		0001294441-05-000010
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050502
FILED AS OF DATE:		20050504
DATE AS OF CHANGE:		20050504

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DYCOM INDUSTRIES INC
		CENTRAL INDEX KEY:			0000067215
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER, SEWER, PIPELINE, COMM AND POWER LINE CONSTRUCTION [1623]
		IRS NUMBER:				591277135
		STATE OF INCORPORATION:			FL
		FISCAL YEAR END:			0729

	BUSINESS ADDRESS:	
		STREET 1:		4440 PGA BLVD. STE 500
		STREET 2:		FIRST UNION CENTER
		CITY:			PALM BEACH GARDENS
		STATE:			FL
		ZIP:			33410
		BUSINESS PHONE:		5616277171

	MAIL ADDRESS:	
		STREET 1:		4440 PGA BLVD STE 500
		STREET 2:		FIRST UNION CENTER
		CITY:			PALM BEACH GARDENS
		STATE:			FL
		ZIP:			33410

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MOBILE HOME DYNAMICS INC
		DATE OF NAME CHANGE:	19820302

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			COE CHARLES B
		CENTRAL INDEX KEY:			0001259298

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10613
		FILM NUMBER:		05799107

	BUSINESS ADDRESS:	
		STREET 1:		250 WILLIAMS STREET
		CITY:			ATLANTA
		STATE:			GA
		ZIP:			30303
		BUSINESS PHONE:		404 302 9700
</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>2005-05-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000067215</issuerCik>
        <issuerName>DYCOM INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>DY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001259298</rptOwnerCik>
            <rptOwnerName>COE CHARLES B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4440 PGA BOULEVARD, SUITE 500</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PALM BEACH GARDENS</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33410</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-05-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>192</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.44</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>383</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>/s/ Michael K. Miller, Attorney-in-Fact for Charles B. Coe</signatureName>
        <signatureDate>2005-05-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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