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    CONFORMED SUBMISSION TYPE:	20-F
    PUBLIC DOCUMENT COUNT:		16
    CONFORMED PERIOD OF REPORT:	20161231
    FILED AS OF DATE:		20170315
    DATE AS OF CHANGE:		20170315

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			GERDAU S.A.
    		CENTRAL INDEX KEY:			0001073404
    		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES & ROLLING & FINISHING MILLS [3310]
    		IRS NUMBER:				000000000
    		STATE OF INCORPORATION:			D5
    		FISCAL YEAR END:			1231

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    		FORM TYPE:		20-F
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-14878
    		FILM NUMBER:		17691025

    	BUSINESS ADDRESS:
    		STREET 1:		AVENIDA FARRAPOS, 1811
    		CITY:			PORTO ALEGRE, RIO GRANDE DO SU
    		STATE:			D5
    		ZIP:			90220-005
    		BUSINESS PHONE:		011-55-51-3323-2703

    	MAIL ADDRESS:
    		STREET 1:		AVENIDA FARRAPOS, 1811
    		CITY:			PORTO ALEGRE, RIO GRANDE DO SU
    		STATE:			D5
    		ZIP:			90220-005

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	GERDAU SA
    		DATE OF NAME CHANGE:	19981112
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