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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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 4l2Ps4eGPQSezll3r9QnEA==

<SEC-DOCUMENT>0001143848-10-000019.txt : 20100510
<SEC-HEADER>0001143848-10-000019.hdr.sgml : 20100510
<ACCEPTANCE-DATETIME>20100510091831
ACCESSION NUMBER:		0001143848-10-000019
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100507
FILED AS OF DATE:		20100510
DATE AS OF CHANGE:		20100510

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ecker Michael J
		CENTRAL INDEX KEY:			0001351140

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-32955
		FILM NUMBER:		10814396

	MAIL ADDRESS:	
		STREET 1:		30 MASSACHUSETTS AVE.
		CITY:			NORTH ANDOVER
		STATE:			MA
		ZIP:			01845

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LSB CORP
		CENTRAL INDEX KEY:			0001143848
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				043557612
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		C/O LSB CORP.
		STREET 2:		30 MASSACHUSETTS AVE.
		CITY:			NORTH ANDOVER
		STATE:			MA
		ZIP:			01845
		BUSINESS PHONE:		978-725-7500

	MAIL ADDRESS:	
		STREET 1:		30 MASSACHUSETTS AVE.
		CITY:			NORTH ANDOVER
		STATE:			MA
		ZIP:			01845
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-05-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001143848</issuerCik>
        <issuerName>LSB CORP</issuerName>
        <issuerTradingSymbol>LSBX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001351140</rptOwnerCik>
            <rptOwnerName>Ecker Michael J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>30 MASSACHUSETTS AVE.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NORTH ANDOVER</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01845</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>300</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24550</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>Michael J. Ecker</signatureName>
        <signatureDate>2010-05-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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