-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 ELq/4/ZZthAjaD65dPxAdZPgBg7XbVavm+mjP2/UOl83SnW/snGNODRE0e3KFDVp
 uVVMaeM67qYt4yb+jIqsHw==

<SEC-DOCUMENT>0000277948-05-000022.txt : 20050517
<SEC-HEADER>0000277948-05-000022.hdr.sgml : 20050517
<ACCEPTANCE-DATETIME>20050517140116
ACCESSION NUMBER:		0000277948-05-000022
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050517
FILED AS OF DATE:		20050517
DATE AS OF CHANGE:		20050517

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Breaux John B
		CENTRAL INDEX KEY:			0001326327

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08022
		FILM NUMBER:		05838127

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		904-366-4242

	MAIL ADDRESS:	
		STREET 1:		CSX CORPORATION
		STREET 2:		500 WATER STREET, C160
		CITY:			JACKSONVILLE
		STATE:			FL
		ZIP:			32202

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CSX CORP
		CENTRAL INDEX KEY:			0000277948
		STANDARD INDUSTRIAL CLASSIFICATION:	RAILROADS, LINE-HAUL OPERATING [4011]
		IRS NUMBER:				621051971
		STATE OF INCORPORATION:			VA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		500 WATER STREET
		STREET 2:		15TH FLOOR
		CITY:			JACKSONVILLE
		STATE:			FL
		ZIP:			32202
		BUSINESS PHONE:		9043593200

	MAIL ADDRESS:	
		STREET 1:		301 WEST BAY STREET
		STREET 2:		21ST FLOOR
		CITY:			JACKSONVILLE
		STATE:			FL
		ZIP:			32202
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-05-17</periodOfReport>

    <issuer>
        <issuerCik>0000277948</issuerCik>
        <issuerName>CSX CORP</issuerName>
        <issuerTradingSymbol>CSX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001326327</rptOwnerCik>
            <rptOwnerName>Breaux John B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>PATTON BOGGS, LLP</rptOwnerStreet1>
            <rptOwnerStreet2>2550 M. STREET NW</rptOwnerStreet2>
            <rptOwnerCity>WASHINGTON</rptOwnerCity>
            <rptOwnerState>DC</rptOwnerState>
            <rptOwnerZipCode>20037</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>2005-05-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>534.645</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>40.915</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>534.645</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trustee</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Exempt payment of director's fees and/or annual retainer in the form of CSX Common Stock pursuant to the CSX Corporate Stock Plan for Directors. The units are payable in cash after the reporting person ceases to be a director or otherwise pursuant to the terms of the CSX Corporation Stock Plan for Directors.</footnote>
        <footnote id="F2">By Trustee, CSX Corporation Stock Plan for Directors.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>John B. Breaux by Gordon F. Bailey, Attorney-in-Fact</signatureName>
        <signatureDate>2005-05-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----