-----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,
 CzH93wRWLQeYXVeYSjcZ/99WiV/YUw1AQYdO/dIWKGKV2VNY8PShI51aMhA76Tah
 zkxrvki6bFt43CwblscZBg==

<SEC-DOCUMENT>0001209191-04-049472.txt : 20041026
<SEC-HEADER>0001209191-04-049472.hdr.sgml : 20041026
<ACCEPTANCE-DATETIME>20041026103301
ACCESSION NUMBER:		0001209191-04-049472
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041025
FILED AS OF DATE:		20041026
DATE AS OF CHANGE:		20041026

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:		041095649

	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>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-10-25</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>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Vice President</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-10-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.30</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Larry Dalesandro</signatureName>
        <signatureDate>2004-10-25</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----