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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-05-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000703604</issuerCik>
        <issuerName>LAWSON PRODUCTS INC/NEW/DE/</issuerName>
        <issuerTradingSymbol>LAWS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001406297</rptOwnerCik>
            <rptOwnerName>King John Bryan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>301 COMMERCE STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1600</rptOwnerStreet2>
            <rptOwnerCity>FORT WORTH</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>76102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-05-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3788</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.8</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3788</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1958204</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares of common stock will have no voting, dividend or transfer rights until May 16, 2018.</footnote>
        <footnote id="F2">Includes (i) 1,689,358 shares held by LKCM Private Discipline Master Fund, SPC, on behalf of its wholly owned subsidiary PDLP Lawson, LLC (PDP), (ii) 26,102 shares held by LKCM Micro-Cap Partnership, L.P. (Micro), (iii) 10,128 shares held by LKCM Core Discipline, L.P. (Core), and (iv) 232,616 shares held by LKCM Headwater Investments II, L.P. (HW). LKCM Private Discipline Management, L.P. holds the management shares of PDP, and LKCM Alternative Management, LLC (PDP GP) is its general partner. LKCM Micro-Cap Management, L.P. (Micro GP) is the general partner of Micro. LKCM Core Discipline Management, L.P. (Core GP) is the general partner of Core. LKCM Headwater Investments II GP, L.P. (HW GP) is the general partner of HW. Mr. King is a controlling member of PDP GP, Micro GP, Core GP, and HW GP. Mr. King expressly disclaims beneficial ownership of the securities reported herein, except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>J. Bryan King</signatureName>
        <signatureDate>2017-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
