FORM 6-K
U.S. SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 
REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE
SECURITIES EXCHANGE ACT OF 1934
 
Dated September 22, 2008
 
Commission File Number 1-14878
 
GERDAU S.A.
(Exact Name as Specified in its Charter)
 
N/A
(Translation of Registrant’s Name)
 
Av. Farrapos 1811
Porto Alegre, Rio Grande do Sul - Brazil CEP 90220-005
(Address of principal executive offices)
 
Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.
 
Form 20-F x
Form 40-F ¨
 
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ¨
 
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ¨
 
Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.
 
Yes ¨
No x
 
If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): Not applicable. 
 
 
 
 
 
SIGNATURES
 
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused the Report to be signed on its behalf by the undersigned, thereunto duly authorized.
 
Date:  September 22, 2008
 
 
GERDAU S.A.
   
 
By: 
/s/Osvaldo Burgos Schirmer       
 
Name: Osvaldo Burgos Schirmer
 
Title: Chief Financial Officer
 
 
 
 
 
EXHIBIT INDEX
 
Exhibit
  
Description of Exhibit
     
99.1
  
Press release, September 11, 2008.