    <SEC-DOCUMENT>0000889331-21-000021-index.html : 20210312
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    <ACCEPTANCE-DATETIME>20210312111003
    ACCESSION NUMBER:		0000889331-21-000021
    CONFORMED SUBMISSION TYPE:	DEF 14A
    PUBLIC DOCUMENT COUNT:		14
    CONFORMED PERIOD OF REPORT:	20201231
    FILED AS OF DATE:		20210312
    DATE AS OF CHANGE:		20210312

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			LITTELFUSE INC /DE
    		CENTRAL INDEX KEY:			0000889331
    		STANDARD INDUSTRIAL CLASSIFICATION:	SWITCHGEAR & SWITCHBOARD APPARATUS [3613]
    		IRS NUMBER:				363795742
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1226

    	FILING VALUES:
    		FORM TYPE:		DEF 14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-20388
    		FILM NUMBER:		21735954

    	BUSINESS ADDRESS:
    		STREET 1:		8755 WEST HIGGINS ROAD
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60631
    		BUSINESS PHONE:		773-628-1000

    	MAIL ADDRESS:
    		STREET 1:		8755 WEST HIGGINS ROAD
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60631
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEF 14A
    <SEQUENCE>1
    <FILENAME>a2021proxystatementdef14a.htm
    <DESCRIPTION>DEF 14A 2021 PROXY STATEMENT
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    Document 1 - file: a2021proxystatementdef14a.htm

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    <FILENAME>daveheinzmann1a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: daveheinzmann1a.jpg

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    <FILENAME>green1a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: green1a.jpg

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    <FILENAME>image051a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 4 - file: image051a.jpg

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    <SEQUENCE>5
    <FILENAME>image061a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 5 - file: image061a.jpg

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    <FILENAME>image071a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 6 - file: image071a.jpg

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    <SEQUENCE>7
    <FILENAME>image091a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 7 - file: image091a.jpg

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    <SEQUENCE>8
    <FILENAME>image111a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 8 - file: image111a.jpg

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    <SEQUENCE>9
    <FILENAME>image131a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: image131a.jpg

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    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: kristinacernigliabw002a011a.jpg

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    <SEQUENCE>11
    <FILENAME>lflogo_taglinexblackjpg3.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 11 - file: lflogo_taglinexblackjpg3.jpg

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    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>proxycard2021_pagex11.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 12 - file: proxycard2021_pagex11.jpg

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    <SEQUENCE>13
    <FILENAME>proxycard2021_pagex21.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 13 - file: proxycard2021_pagex21.jpg

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    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>14
    <FILENAME>stafford_sig1a.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 14 - file: stafford_sig1a.jpg

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