<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-02-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000021759</issuerCik>
        <issuerName>COLLINS INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>COLL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001297972</rptOwnerCik>
            <rptOwnerName>Boston Avenue Capital</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>415 S. BOSTON</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TULSA</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>74103</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-02-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>32500</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.7</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>668805</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Purchased directly by Boston Avenue Capital, LLC</footnote>
        <footnote id="F2">Amount held directly by Boston Avenue Capital, LLC.</footnote>
    </footnotes>

    <remarks>This is a joint filing with Boston Avenue Capital, LLC, Yorktown Capital, LLC, Value Fund Advisors, LLC and Charles Gillman.  VFA is the manager of Boston Avenue and Yorktown.  Mr. Gillman is the manager and a member of VFA.  All entities and persons are located at the same address as Boston Avenue.  In addition to the shares held by Boston Aveunue as indicated above, the following entities own the following number of shares:

Yorktown Avenue Capital - 103,738
Value Fund Advisors - 770,543 held indirectly, VFA disclaims beneficial ownership of these shares.
Charles Gillman - 770, 543 held indirectly, Mr. Gillman disclaims beneficial ownership of these shaers.</remarks>

    <ownerSignature>
        <signatureName>Frederic Dorwart</signatureName>
        <signatureDate>2006-02-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
