SC 13D/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No. 5)*

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 24, 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 287,375,350
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 287,375,350
	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) 66.3%
	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 287,375,350
			9.	Sole Dispositive Power 0
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 287,375,350
	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) 66.3%
	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 435,668
			8.	Shared Voting Power 287,375,350
			9.	Sole Dispositive Power 435,668
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 287,811,018
	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) 66.4%
	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 1,009,232
			8.	Shared Voting Power 287,375,350
			9.	Sole Dispositive Power 1,009,232
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 288,384,582
	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) 66.6%
	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 76,000
			8.	Shared Voting Power 287,375,350
			9.	Sole Dispositive Power 76,000
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 287,451,350
	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) 66.3%
	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 17,600
			8.	Shared Voting Power 287,375,350
			9.	Sole Dispositive Power 17,600
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 287,392,950
	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) 66.3%
	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 425,668
			8.	Shared Voting Power 287,375,350
			9.	Sole Dispositive Power 425,668
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 287,801,018
	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) 66.4%
	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 946,232
			8.	Shared Voting Power 287,375,350
			9.	Sole Dispositive Power 946,232
			10.	Shared Dispositive Power 287,375,350
	11.	Aggregate Amount Beneficially Owned by Each Reporting Person 288,321,582
	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) 66.5%
	14.	Type of Reporting Person (See Instructions) IN

9

Amendment No. 5 to Schedule 13D
	This Amendment No. 5 to Schedule 13D (“Amendment No. 5”) amends and supplements Item 4 and amends and supplements Item 7 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 July 9, 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. 5 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
	This Amendment No. 5 includes as Exhibit 1 a press release dated August 24, 2010, entitled “Gerdau Ameristeel Shareholders Approve Plan of Arrangement” issued by the Issuer and Gerdau S.A.
Item 7.	Material to be Filed as Exhibits
	The following document is filed as an exhibit:

Exhibit Number	Exhibit Name
1	Press Release dated August 24, 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 24, 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

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EX-1

Exhibit 1

NOTICE TO THE MARKET

GERDAU AMERISTEEL SHAREHOLDERS APPROVE PLAN OF ARRANGEMENT

Gerdau S.A. (Bovespa: GGBR, NYSE: GGB, Latibex: XGGB) and Gerdau Ameristeel Corporation (TSX: GNA, NYSE: GNA) announced today that Gerdau Ameristeel’s shareholders passed a special resolution to approve an arrangement under the Canada Business Corporations Act 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 in cash for each common share. The special resolution was approved by approximately 93% of the votes cast by holders of common shares and approximately 74% of the votes cast by “minority” holders of common shares (shareholders other than Gerdau S.A. and its related parties) at Gerdau Ameristeel’s special meeting of shareholders. It is expected that the arrangement will be completed in August 2010, following the receipt of court approval and the satisfaction of other 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, court approvals and the satisfaction or waiver of certain other 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 24th, 2010.

Osvaldo Burgos Schirmer

Executive Vice-President and

Investor Relations Officer

2