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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>0001209191-03-021063.txt : 20030911
<SEC-HEADER>0001209191-03-021063.hdr.sgml : 20030911
<ACCEPTANCE-DATETIME>20030911115121
ACCESSION NUMBER:		0001209191-03-021063
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030909
FILED AS OF DATE:		20030911

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WHITE R ELTON
		CENTRAL INDEX KEY:			0001198935

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09965
		FILM NUMBER:		03891282

	MAIL ADDRESS:	
		STREET 1:		8330 SANDERLING RD
		CITY:			SARASOTA
		STATE:			FL
		ZIP:			34242

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KEITHLEY INSTRUMENTS INC
		CENTRAL INDEX KEY:			0000054991
		STANDARD INDUSTRIAL CLASSIFICATION:	INSTRUMENTS FOR MEAS & TESTING OF ELECTRICITY & ELEC SIGNALS [3825]
		IRS NUMBER:				340794417
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		28775 AURORA RD
		CITY:			SOLON
		STATE:			OH
		ZIP:			44139
		BUSINESS PHONE:		2162480400
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc4a.xml
<DESCRIPTION>FORM 4/A SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?><ownershipDocument><schemaVersion>X0201</schemaVersion>    <documentType>4/A</documentType><periodOfReport>2003-09-09</periodOfReport><dateOfOriginalSubmission>2003-09-11</dateOfOriginalSubmission><notSubjectToSection16>0</notSubjectToSection16><issuer><issuerCik>0000054991</issuerCik><issuerName>KEITHLEY INSTRUMENTS INC</issuerName>        <issuerTradingSymbol>KEI</issuerTradingSymbol></issuer><reportingOwner><reportingOwnerId><rptOwnerCik>0001198935</rptOwnerCik><rptOwnerName>WHITE R ELTON</rptOwnerName></reportingOwnerId><reportingOwnerAddress><rptOwnerStreet1>KEITHLEY INSTRUMENTS, INC.</rptOwnerStreet1><rptOwnerStreet2>28775 AURORA ROAD</rptOwnerStreet2><rptOwnerCity>SOLON</rptOwnerCity><rptOwnerState>OH</rptOwnerState><rptOwnerZipCode>44139</rptOwnerZipCode><rptOwnerStateDescription></rptOwnerStateDescription></reportingOwnerAddress><reportingOwnerRelationship><isDirector>1</isDirector><isOfficer>0</isOfficer><isTenPercentOwner>0</isTenPercentOwner><isOther>0</isOther></reportingOwn
erRelationship></reportingOwner><derivativeTable><derivativeHolding><securityTitle><value>Common Stock Option</value></securityTitle><conversionOrExercisePrice><value>36.85</value></conversionOrExercisePrice><exerciseDate><value>2001-08-18</value></exerciseDate><expirationDate><value>2011-02-17</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stk</value></underlyingSecurityTitle><underlyingSecurityShares><value>10000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>10000</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Common Stock Option</value></securityTitle><conversionOrExercisePrice><value>19.23</value></conversionOrExercisePrice><exerciseDate><value>2002-08-17</value></exerciseDate><expirationDate>
<value>2012-02-16</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stk</value></underlyingSecurityTitle><underlyingSecurityShares><value>10000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>10000</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeHolding><derivativeHolding><securityTitle><value>Common Stock Option</value></securityTitle><conversionOrExercisePrice><value>10.7</value></conversionOrExercisePrice><exerciseDate><value>2003-08-16</value></exerciseDate><expirationDate><value>2013-02-15</value></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stk</value></underlyingSecurityTitle><underlyingSecurityShares><value>10000</value></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTr
ansaction><value>10000</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeHolding><derivativeTransaction><securityTitle><value>Phantom Stock Units</value></securityTitle><conversionOrExercisePrice><value>16.6375</value><footnoteId id="F2" /></conversionOrExercisePrice><transactionDate><value>2003-09-08</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>225.69</value><footnoteId id="F2" /></transactionShares><transactionPricePerShare><value>0</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmount
s><exerciseDate><footnoteId id="F3" /></exerciseDate><expirationDate><footnoteId id="F3" /></expirationDate><underlyingSecurity><underlyingSecurityTitle><value>Common Stk</value></underlyingSecurityTitle><underlyingSecurityShares><value>225.69</value><footnoteId id="F4" /></underlyingSecurityShares></underlyingSecurity><postTransactionAmounts><sharesOwnedFollowingTransaction><value>25023.21</value><footnoteId id="F5" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></derivativeTransaction></derivativeTable><footnotes><footnote id="F1">AMENDED - Previously listed as dollars.  Correct listing is number of shares.</footnote><footnote id="F2">No change made from original filing</footnote><footnote id="F3">The phantom stock units were accrued under the Keithley Instruments, Inc. Deferred Stock Plan and are to be settled in common stock upon the retirement from the Board of the reporting person; re
tirement date is not yet known.</footnote><footnote id="F4">AMENDED - Previously listed as dollars.  Correct entry is shares.</footnote><footnote id="F5">Phantom shares were acquired on various dates (beginning 09/19/1995) with prices ranging from $2.469 to $64.00.</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>Mark J. Plush, Attorney-in Fact</signatureName><signatureDate>2003-09-11</signatureDate></ownerSignature></ownershipDocument>

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</DOCUMENT>
</SEC-DOCUMENT>
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