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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-07-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000027613</issuerCik>
        <issuerName>DECORATOR INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>DII</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001105838</rptOwnerCik>
            <rptOwnerName>ROBOTTI ROBERT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity></rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></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, Par Value $0.20 Per Share</value>
            </securityTitle>
            <transactionDate>
                <value>2004-07-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2050</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.639</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>449057</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, Par Value $0.20 Per Share</value>
            </securityTitle>
            <transactionDate>
                <value>2004-08-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.5</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>451057</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F7"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This amount of 2,050 shares of the Common Stock, Par Value $0.20 per share (the &quot;Common Stock&quot;) should have been reported on or before July 20, 2004, but due to an oversite this amount was not reported.</footnote>
        <footnote id="F2">This amount includes 321,974 shares of the Common Stock directly owned by the discretionary accounts of Robotti &amp; Company, LLC (&quot;Robotti &amp; Company&quot;), a broker-dealer registered under Section 15 of the Securities Exchange Act of 1934 (&quot;Exchange Act&quot;), and by the advisory clients of Robotti &amp; Company Advisors, LLC (&quot;Robotti &amp; Company Advisors&quot;) registered under the Investment Advisors Act of 1940 and beneficially owned by its discretionary brokerage customers and advisory clients.</footnote>
        <footnote id="F3">This amount includes 122,318 shares of the Common Stock directly owned by the Ravenswood Investment Company, L.P. (&quot;RIC&quot;) and beneficially owned by its partners.</footnote>
        <footnote id="F4">This amount includes 4,765 shares of the Common Stock directly owned by Mr. Robotti and is held in his brokerage account.  Mr. Robotti claims beneficial ownership of such securities.</footnote>
        <footnote id="F5">Mr. Robotti is deemed to beneficially own (solely for the purpose of Rule 16a-1(a)(2) under the Exchange Act) the securities set forth in footnotes (2) and (3) above through his proportionate ownership of Robotti &amp; Company and Robotti &amp; Company Advisors, by virtue of the investment discretion Robotti and Company and Robotti &amp; Company Advisors have over the accounts of its brokerage customers and advisory clients, and as managing member of Ravenswood Management Company, L.L.C. which serves as the general partner of RIC.  Mr. Robotti disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F6">This amount includes 323,974 shares of the Common Stock directly owned by the discretionary accounts of Robotti &amp; Company and by the advisory clients of Robotti &amp; Company Advisors and beneficially owned by its discretionary brokerage customers and advisory clients.</footnote>
        <footnote id="F7">Mr. Robotti is deemed to beneficially own (solely for the purpose of Rule 16a-1(a)(2) under the Exchange Act) the securities set forth in footnotes (3) and (6) above through his proportionate ownership of Robotti &amp; Company and Robotti &amp; Company Advisors, by virtue of the investment discretion Robotti and Company and Robotti &amp; Company Advisors have over the accounts of its brokerage customers and advisory clients, and as managing member of Ravenswood Management Company, L.L.C. which serves as the general partner of RIC.  Mr. Robotti disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Robert E. Robotti</signatureName>
        <signatureDate>2004-08-10</signatureDate>
    </ownerSignature>
</ownershipDocument>

