SC 13D/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No. 6)*

GERDAU AMERISTEEL CORPORATION

(Name of Issuer)

COMMON SHARES

(Title of Class of Securities)

37373P 10 5

(CUSIP Number)

Alan M. Klein

Simpson Thacher & Bartlett LLP

425 Lexington Avenue

New York, NY 10017

(212) 455-2000

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

August 30, 2010

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d–7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Gerdau S.A.
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) OO
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) CO

2

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Gerdau Steel North America Inc.
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) AF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Canada
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) CO

3

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Jorge Gerdau Johannpeter
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) PF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) IN

4

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Frederico Carlos Gerdau Johannpeter
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) PF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) IN

5

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Andre Gerdau Johannpeter
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) PF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) IN

6

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Claudio Gerdau Johannpeter
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) PF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) IN

7

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Germano Gerdau Johannpeter
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) PF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) IN

8

CUSIP No.   37373P 10 5
	1.	Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only) Klaus Gerdau Johannpeter
	2.	Check the Appropriate Box if a Member of a Group (See Instructions)
		(a)			x
		(b)			o
	3.	SEC Use Only
	4.	Source of Funds (See Instructions) PF
	5.	Check if Disclosure of Legal Proceedings Is Required Pursuant to Items 2(d) or 2(e)  o
	6.	Citizenship or Place of Organization Federative Republic of Brazil
Number of Shares Beneficially Owned by Each Reporting Person With			7.	Sole Voting Power 0
			8.	Shared Voting Power 433,773,874
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 433,773,874
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 433,773,874
	12.	Check if the Aggregate Amount in Row (11) Excludes Certain Shares (See Instructions)o
	13.	Percent of Class Represented by Amount in Row (11) 100.0%
	14.	Type of Reporting Person (See Instructions) IN

9

Amendment No. 6 to Schedule 13D

This Amendment No. 6 to Schedule 13D (“Amendment No. 6”) amends and supplements Item 4 and Item 7 and restates clauses (a) and (c) of the Schedule 13D filed by Gerdau S.A., Gerdau Steel North America Inc. (“GSNAI”) and Jorge Gerdau Johannpeter, Frederico Carlos Gerdau Johannpeter, Claudio Gerdau Johannpeter, Klaus Gerdau Johannpeter, Germano Gerdau Johannpeter and Andre Gerdau Johannpeter (collectively, the “Gerdau Johannpeter family” and together with Gerdau S.A. and Gerdau Steel North America Inc., the “Reporting Persons”) on August 24, 2010, as previously amended and supplemented, (the “Schedule 13D”), in respect of the common shares, no par value, of Gerdau Ameristeel Corporation (the “Issuer”), a corporation incorporated under the laws of Canada.  Capitalized terms used in this Amendment No. 6 but not defined herein have the meanings given to such terms in the Schedule 13D.  Except as specifically provided herein, this Amendment does not modify any of the information previously reported in the Schedule 13D.

Item 4.Purpose of Transaction

The Issuer announced on August 30, 2010 that Gerdau S.A., through its wholly-owned subsidiary GSNAI, acquired all of the remaining issued and outstanding Common Shares of the Issuer not already owned, directly or indirectly, by it by way of a plan of arrangement for US$11.00 in cash per share (the “Arrangement”).  Gerdau S.A. now beneficially owns 100% of the Common Shares of the Issuer.

The Common Shares of the Issuer ceased trading on the New York Stock Exchange (the “NYSE”) before the market opened on August 30, 2010 and the Company has requested that the NYSE file a notification of removal from listing on a Form 25 with the SEC.  Delisting of the Common Shares of the Issuer from the Toronto Stock Exchange is expected to occur on or about August 31, 2010.  Concurrent with the delisting of the Common Shares, the Issuer will apply to all applicable Canadian securities regulatory authorities and to the Securities and Exchange Commission in order to cease to be a reporting issuer, and to withdraw its shares from registration, respectively.

Item 5.Interest in Securities of the Issuer

(a)  Gerdau S.A. beneficially owns 433,773,874 Common Shares of the Issuer or 100% of the Common Shares of the Issuer.

(c)  On August 30, 2010, Gerdau S.A. through its wholly-owned subsidiary GSNAI, acquired 145,331,071 Common Shares of the Issuer pursuant to the Arrangement.

Item 7.Material to be Filed as Exhibits

The following documents are filed as exhibits:

Exhibit Number	Exhibit Name
1	Press Release dated August 27, 2010
2	Press Release dated August 30, 2010

10

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: August 30, 2010

GERDAU S.A.
By:	/s/ Osvaldo Burgos Schirmer
Name: Osvaldo Burgos Schirmer
Title: Chief Financial Officer
GERDAU STEEL NORTH AMERICA INC.
By:	/s/ Expedito Luz
Name: Expedito Luz
Title: Assistant Secretary
/s/ Jorge Gerdau Johannpeter
Jorge Gerdau Johannpeter
/s/ Frederico C. Gerdau Johannpeter
Frederico C. Gerdau Johannpeter
/s/ Andre Gerdau Johannpeter
Andre Gerdau Johannpeter
/s/ Claudio Gerdau Johannpeter
Claudio Gerdau Johannpeter
/s/ Germano Gerdau Johannpeter
Germano Gerdau Johannpeter
/s/ Klaus Gerdau Johannpeter
Klaus Gerdau Johannpeter

11

EX-1

Exhibit 1

NOTICE TO THE MARKET

GERDAU AMERISTEEL OBTAINS FINAL ORDER FOR PLAN OF ARRANGEMENT

Gerdau S.A. (Bovespa: GGBR, NYSE: GGB, Latibex: XGGB) and Gerdau Ameristeel Corporation (TSX: GNA, NYSE: GNA) announced today that the Ontario Superior Court of Justice has issued a final order approving the previously announced plan of arrangement (the “Arrangement”) involving, among other things, the acquisition by Gerdau S.A. of all of the issued and outstanding common shares of Gerdau Ameristeel not already owned, directly or indirectly, by it for US$ 11.00 per share. The Arrangement is currently scheduled to close on Monday, August 30, 2010, following the satisfaction of certain customary conditions.

About Gerdau S.A.

Gerdau S.A. is the leading producer of long steel in the Americas and one of the world’s largest suppliers of specialty long steel. It has plants in 14 countries spanning the Americas, Europe and Asia, with total installed capacity of more than 25 million metric tons of steel. It is the largest recycler in Latin America, transforming millions of metric tons of scrap into steel every year. With over 140,000 shareholders, Gerdau S.A.’s publicly-held companies are listed in the stock exchanges of São Paulo (Bovespa: GGBR4, GGBR3, GOAU4, GOAU3 and AVIL3), New York (NYSE: GNA, GGB), Toronto (TSX: GNA), Madrid (Latibex: XGGB) and Lima (BVL: SIDERC1).

About Gerdau Ameristeel

Gerdau Ameristeel is the second largest mini-mill steel producer in North America, with annual manufacturing capacity of approximately 10 million metric tons of mill finished steel products. Through its vertically integrated network of mini-mills, scrap recycling facilities and downstream operations, Gerdau Ameristeel serves customers throughout the United States and Canada. The Company’s products are generally sold to steel service centers, steel fabricators, or directly to original equipment manufacturers for use in a variety of industries, including non-residential, infrastructure, commercial, industrial and residential construction, metal building, manufacturing, automotive, mining, cellular and electrical transmission and equipment manufacturing. Gerdau Ameristeel’s majority shareholder is Gerdau S.A.

Forward Looking Statements

This release contains forward-looking statements relating to the acquisition by Gerdau S.A. of the shares of Gerdau Ameristeel that Gerdau S.A. does not already own, including statements

regarding the completion of the proposed transaction and other statements that are not historical facts. Such forward-looking statements are subject to important risks and uncertainties including, without limitation, the satisfaction or waiver of certain conditions contemplated by the definitive arrangement agreement. As a result of these risks and uncertainties, the proposed transaction could be modified, restructured or not be completed, and the results or events predicted in these forward-looking statements may differ materially from actual results or events. These forward-looking statements are not guarantees of future performance, given that they involve risks and uncertainties. Gerdau S.A. and Gerdau Ameristeel do not assume and expressly renounce any obligation to update any of these forward-looking statements, which are only applicable on the date on which they were made. Additionally, Gerdau S.A. and Gerdau Ameristeel undertake no obligation to comment on expectations of, or statements made by third parties in respect of the proposed transaction.

Rio de Janeiro, August 27th, 2010.

Osvaldo Burgos Schirmer

Executive Vice-President and

Investor Relations Officer

2

EX-2

Exhibit 2

NOTICE TO THE MARKET

GERDAU AMERISTEEL CORPORATION AND GERDAU S.A. ANNOUNCE CLOSING OF TRANSACTION

Gerdau S.A. (Bovespa: GGBR, NYSE: GGB, Latibex: XGGB) and Gerdau Ameristeel Corporation (TSX: GNA, NYSE: GNA) announced the completion today of the acquisition of Gerdau Ameristeel by way of a Plan of Arrangement (the “Arrangement”).

Pursuant to the Arrangement, Gerdau S.A. acquired all of the issued and outstanding common shares of Gerdau Ameristeel not already owned, directly or indirectly, by it for US$11.00 in cash per share. Any questions or requests for assistance in surrendering certificates representing shares of Gerdau Ameristeel in order to receive consideration for such shares may be directed to the office of the depositary, CIBC Mellon Trust Company, at 416-643-5500 or toll free at 1-800-387-0825 or by email at inquiries@cibcmellon.com. Non-registered shareholders should contact their broker or other intermediary for details.

De-listing of the common shares of Gerdau Ameristeel from the Toronto Stock Exchange and the New York Stock Exchange is expected to occur shortly. Concurrent with the delisting of its common shares, Gerdau Ameristeel will apply to all applicable Canadian securities regulatory authorities and to the Securities and Exchange Commission in order to cease to be a reporting issuer, and to withdraw its shares from registration, respectively.

About Gerdau S.A.

Gerdau S.A. is the leading producer of long steel in the Americas and one of the world’s largest suppliers of specialty long steel. It has plants in 14 countries spanning the Americas, Europe and Asia, with total installed capacity of more than 25 million metric tons of steel. It is the largest recycler in Latin America, transforming millions of metric tons of scrap into steel every year. With over 140,000 shareholders, Gerdau S.A.’s publicly-held companies are listed in the stock exchanges of Sao Paulo (Bovespa: GGBR4, GGBR3, GOAU4, GOAU3 and AVIL3), New York (NYSE: GNA, GGB), Toronto (TSX: GNA), Madrid (Latibex: XGGB) and Lima (BVL: SIDERC1).

About Gerdau Ameristeel

Gerdau Ameristeel is the second largest mini-mill steel producer in North America, with annual manufacturing capacity of approximately 10 million metric tons of mill finished steel products. Through its vertically integrated network of mini-mills, scrap recycling facilities and downstream operations, Gerdau Ameristeel serves customers throughout the United States and Canada. The Company’s products are generally sold to steel service centers, steel fabricators, or directly to original equipment manufacturers for use in a variety of industries, including non-residential, infrastructure, commercial, industrial and residential construction, metal building, manufacturing, automotive, mining, cellular and electrical transmission and equipment manufacturing. Gerdau Ameristeel’s majority shareholder is Gerdau S.A.

Rio de Janeiro, August 30th, 2010.

Osvaldo Burgos Schirmer

Executive Vice-President and

Investor Relations Officer