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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-10-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000892553</issuerCik>
        <issuerName>CHART INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>CIDI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000949509</rptOwnerCik>
            <rptOwnerName>OAKTREE CAPITAL MANAGEMENT LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>333 SOUTH GRAND AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>28TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90071</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001049809</rptOwnerCik>
            <rptOwnerName>OCM PRINCIPAL OPPORTUNITIES FUND II LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>333 SOUTH GRAND AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>28TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90071</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>2004-10-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>366368</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2463638</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person, Oaktree Capital Management, LLC (&quot;Oaktree&quot;), is a registered investment adviser under the Investment Advisers Act of 1940, as amended, acting as the general partner of OCM Principal Opportunities Fund II, L.P., a Delaware limited partnership (&quot;OCM Fund&quot;).</footnote>
        <footnote id="F2">The OCM Fund is the direct beneficial owner of the Common Stock.  Oaktree disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein. The filing of this Form 4 shall not be deemed an admission that Oaktree is the beneficial owner of any securities not held directly for its account for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise.</footnote>
        <footnote id="F3">Oaktree is a limited liability company managed by an executive committee, the members of which are Howard S. Marks, Bruce A. Karsh, David Kirchheimer, Sheldon M. Stone, D. Richard Masson, Larry W. Keele, Stephen A. Kaplan, Russel S. Bernard, John W. Moon, Kevin L. Clayton, and John B. Frank. Each of such persons may be deemed a beneficial owner of the securities listed herein by virtue of such status as members of Oaktree. Each such person disclaims beneficial ownership of the securities listed herein and the filing of this Form 4 shall not be construed as an admission that such person is the beneficial owner of any securities covered by this Form 4, except to the extent of any pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Oaktree Capital Management, LLC Stephen A. Kaplan, Principal and Richard Ting, Vice President, Legal</signatureName>
        <signatureDate>2004-10-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>OCM Principal Opportunities Fund II, L.P. By: Oaktree Capital Management, LLC, its general partner Stephen A. Kaplan, Principal and Richard Ting, Vice President, Legal</signatureName>
        <signatureDate>2004-10-05</signatureDate>
    </ownerSignature>
</ownershipDocument>

