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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001140361-10-018683.txt : 20100504
<SEC-HEADER>0001140361-10-018683.hdr.sgml : 20100504
<ACCEPTANCE-DATETIME>20100504094548
ACCESSION NUMBER:		0001140361-10-018683
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100503
FILED AS OF DATE:		20100504
DATE AS OF CHANGE:		20100504

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SHEAR HEIDI L BROWN
		CENTRAL INDEX KEY:			0001258647

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07677
		FILM NUMBER:		10795230

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SHEAR DAVID MICHAEL
		CENTRAL INDEX KEY:			0001258649

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07677
		FILM NUMBER:		10795229

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LSB INDUSTRIES INC
		CENTRAL INDEX KEY:			0000060714
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INORGANIC CHEMICALS [2810]
		IRS NUMBER:				731015226
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		16 S PENNSYLVANIA
		CITY:			OKLAHOMA CITY
		STATE:			OK
		ZIP:			73101
		BUSINESS PHONE:		4052354546

	MAIL ADDRESS:	
		STREET 1:		16 SOUTH PENNSYLVANIA
		CITY:			OKLAHOMA CITY
		STATE:			OK
		ZIP:			73101
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-05-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000060714</issuerCik>
        <issuerName>LSB INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>LXU</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001258649</rptOwnerCik>
            <rptOwnerName>SHEAR DAVID MICHAEL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>16 SOUTH PENNSYLVANIA AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>OKLAHOMA CITY</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>73107</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP/General Counsel/Sec</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001258647</rptOwnerCik>
            <rptOwnerName>SHEAR HEIDI L BROWN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>16 SOUTH PENNSYLVANIA AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>OKLAHOMA CITY</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>73107</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP/Managing Counsel/Asst Sec</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-05-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18.50</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>83081</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trusts</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8988</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The designated reporting person is David M. Shear.  Mr. Shear's spouse, Heidi L. Brown Shear, jointly files this report with Mr. Shear.  Heidi Shear is Vice President, Managing Counsel and Assistant Secretary of the Issuer.  These shares are held in an account jointly owned by David Shear's revocable trust, of which he is settlor and trustee, and Heidi Shear's revocable trust, of which she is settlor and trustee.  This amount does not include, and David Shear disclaims beneficial ownership of 8,988 shares held by two trusts established for the benefit of each of the reporting persons' children.  Please see footnote (3) for a description of the children's trusts.</footnote>
        <footnote id="F2">These shares were sold pursuant to the terms of the reporting persons' Programmed Plan of Transactions under Rule 10b5-1, dated June 15, 2009.</footnote>
        <footnote id="F3">These shares are held by two trusts established for the benefit of each of the reporting persons' children, of which Heidi Shear is the trustee and exercises investment and dispositive control over the trusts' portfolio securities.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Heidi L. Brown Shear</signatureName>
        <signatureDate>2010-05-03</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>David M. Shear</signatureName>
        <signatureDate>2010-05-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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