<SEC-DOCUMENT>0001140361-12-014236.txt : 20120308
<SEC-HEADER>0001140361-12-014236.hdr.sgml : 20120308
<ACCEPTANCE-DATETIME>20120308174315
ACCESSION NUMBER:		0001140361-12-014236
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120307
FILED AS OF DATE:		20120308
DATE AS OF CHANGE:		20120308

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LAWRENCE CHARLES BERDON
		CENTRAL INDEX KEY:			0001097491

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07615
		FILM NUMBER:		12678291

	MAIL ADDRESS:	
		STREET 1:		PO BOX 1343
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77251-1343

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KIRBY CORP
		CENTRAL INDEX KEY:			0000056047
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER TRANSPORTATION [4400]
		IRS NUMBER:				741884980
		STATE OF INCORPORATION:			NV
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		55 WAUGH DRIVE SUITE 1000
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77385
		BUSINESS PHONE:		7134351000

	MAIL ADDRESS:	
		STREET 1:		P.O. BOX 1745
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77251

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KIRBY EXPLORATION CO INC
		DATE OF NAME CHANGE:	19900510
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0304</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-03-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000056047</issuerCik>
        <issuerName>KIRBY CORP</issuerName>
        <issuerTradingSymbol>KEX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001097491</rptOwnerCik>
            <rptOwnerName>LAWRENCE CHARLES BERDON</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>55 WAUGH DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1000</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77007</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $.10 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-07</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>30000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>68.053</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>170000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Trusts</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $.10 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6800</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>68.2306</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>163200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Trusts</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $.10 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>171060</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $.10 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>34227</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Partnerships</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, par value $.10 per share</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10111</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>401K Plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The reported price is the weighted average sales price.  The sales were at prices ranging from $67.91 to $68.45 per share.  The reporting person will provide, upon request by the Commission staff, full information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F2">The reported price is the weighted average sales price.  The sales were at prices ranging from $67.72 to $68.68 per share.  The reporting person will provide, upon request by the Commission staff, full information regarding the number of shares sold at each separate price.</footnote>
        <footnote id="F3">These shares are owned by trusts for the benefit of members of Mr. Lawrence's family.  Mr. Lawrence is not a beneficiary of the trusts, but under their terms, he has the right to acquire the property in the trusts, including the Kirby shares owned by the trusts, by substituting property of equal value.</footnote>
        <footnote id="F4">The reported shares are held by Lawrence Family Interests, LP, a limited partnership of which entities wholly owned by Mr. Lawrence and his wife are the general partners and of which Mr. Lawrence's children and trusts for their benefit are the limited partners.  Mr. Lawrence disclaims beneficial ownership of the shares owned by the limited partnership except to the extent of his pecuniary interest in such shares.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>G. Stephen Holcomb, Agent and Attorney-in-Fact</signatureName>
        <signatureDate>2012-03-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
