6-K

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                                    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 1, 2005


                         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.


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                                   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 1, 2005

                                    GERDAU S.A.




                                    By:  /s/ Osvaldo Burgos Schirmer
                                         ---------------------------------------
                                          Name:  Osvaldo Burgos Schirmer
                                          Title: Chief Financial Officer




                                  EXHIBIT INDEX




Exhibit               Description of Exhibit
- -------               ----------------------

99.1                  Release, August 31, 2005

EX-99.1

                                                                    Exhibit 99.1



                                  ANNOUNCEMENT


Gerdau S.A. ("Gerdau") announced today that it intends to offer its Guaranteed
Perpetual Bonds by means of a private placement to qualified institutional
buyers under Rule 144A, and in offshore transactions pursuant to Regulation S,
under the Securities Act of 1933, as amended (the "Securities Act"). The bonds
will be guaranteed by four of Gerdau's Brazilian subsidiaries: Gerdau Acominas
S.A., Gerdau Acos Longos S.A., Gerdau Acos Especiais S.A. and Gerdau Comercial
de Acos S.A. The aggregate principal amount of the bonds is anticipated to be
US$250,000,000. Net proceeds of the offering will be used for general corporate
purposes of Gerdau and its subsidiaries.

The bonds and the guarantees of the bonds have not been and will not be
registered under the Securities Act and may not be offered or sold in the United
States absent registration or an applicable exemption from registration
requirements.

This announcement does not constitute an offer to sell or the solicitation of
offers to buy any security and shall not constitute an offer, solicitation or
sale of any security in any jurisdiction in which such offer, solicitation or
sale would be unlawful. This announcement is being issued pursuant to and in
accordance with Rule 135(c) under the Securities Act.

This announcement contains forward-looking statements that involve a number of
risks and uncertainties. These statements are based on current expectations
whereas actual results may differ. Among the factors that could cause actual
results to differ are the risk factors listed in Gerdau's 2004 Annual Report on
Form 20F or periodic filings with the Securities and Exchange Commission.

This announcement is only being distributed to and is only directed at (i)
persons who are outside the United Kingdom or (ii) to investment professionals
falling within Article 19(5) of the Financial Services and Markets Act 2000
(Financial Promotion) Order 2005 (the "Order") or (iii) high net worth entities,
and other persons to whom it may lawfully be communicated, falling within
Article 49(2) of the Order (all such persons together being referred to as
"relevant persons"). The bonds are only available to, and any invitation, offer
or agreement to subscribe, purchase or otherwise acquire such bonds will be
engaged in only with, relevant persons. Any person who is not a relevant person
should not act or rely on this communication or any of its contents.

This announcement is not for distribution in Canada, Japan or Australia.


                        Rio de Janeiro, August 31, 2005.

                             Osvaldo Burgos Schirmer
                            Executive Vice-President
                         Director of Investor Relations