-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 DgfasN5GPmrzFN/puXx74EvDpFITA8XzhaV8kksgEQRTCSBOwKYne4dNtfLZi607
 mBrht6iKnsTmRw6ksDMvlg==

<SEC-DOCUMENT>0001209191-08-062525.txt : 20081124
<SEC-HEADER>0001209191-08-062525.hdr.sgml : 20081124
<ACCEPTANCE-DATETIME>20081124173724
ACCESSION NUMBER:		0001209191-08-062525
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20081121
FILED AS OF DATE:		20081124
DATE AS OF CHANGE:		20081124

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SMITH KEVIN
		CENTRAL INDEX KEY:			0001277221

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31298
		FILM NUMBER:		081211481

	BUSINESS ADDRESS:	
		STREET 1:		C/O LANNETT CO INC
		STREET 2:		9000 STATE ROAD
		CITY:			PHILADELPHIA
		STATE:			PA
		ZIP:			19138
		BUSINESS PHONE:		2153339000

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LANNETT CO INC
		CENTRAL INDEX KEY:			0000057725
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				230787699
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		9000 STATE RD
		CITY:			PHILADELPHIA
		STATE:			PA
		ZIP:			19136
		BUSINESS PHONE:		2153339000

	MAIL ADDRESS:	
		STREET 1:		9000 STATE ROAD
		STREET 2:		9000 STATE ROAD
		CITY:			PHLADELPHIA
		STATE:			PA
		ZIP:			19136

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NETHERLANDS SECURITIES INC
		DATE OF NAME CHANGE:	19660629
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-11-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000057725</issuerCik>
        <issuerName>LANNETT CO INC</issuerName>
        <issuerTradingSymbol>LCI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001277221</rptOwnerCik>
            <rptOwnerName>SMITH KEVIN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9000 STATE ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PHILADELPHIA</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19136</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-11-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.10</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2336</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Brian J. Kearns, as attorney in fact for Kevin Smith</signatureName>
        <signatureDate>2008-11-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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