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                          GERDAU AMERISTEEL CORPORATION
                              Hopkins Street South
                                 Whitby, Ontario
                                     L1N 5T1

                                  FORM OF PROXY

     THIS PROXY IS SOLICITED BY MANAGEMENT OF GERDAU AMERISTEEL CORPORATION
        IN RESPECT OF THE ANNUAL AND SPECIAL MEETING OF THE SHAREHOLDERS
                             TO BE HELD MAY 6, 2005

The undersigned shareholder of GERDAU AMERISTEEL CORPORATION ("Gerdau
Ameristeel") hereby appoints, Phillip E. Casey, President and Chief Executive
Officer, or failing him, Tom J. Landa, Vice-President-Finance, Chief Financial
Officer and Assistant Secretary, both being officers of Gerdau Ameristeel, or
instead of any of the foregoing ................................, as nominee of
the undersigned, to attend, vote and act for and on behalf of the undersigned AT
THE ANNUAL AND SPECIAL MEETING OF SHAREHOLDERS OF GERDAU AMERISTEEL TO BE HELD
ON MAY 6, 2005 AND AT ALL ADJOURNMENTS THEREOF, upon the following matters:

(a)   ELECTION OF DIRECTORS

      The proposed nominees named in the accompanying management information
      circular are:

      Phillip E. Casey, Kenneth W. Harrigan, Joseph J. Heffernan, Jorge Gerdau
      Johannpeter, Frederico C. Gerdau Johannpeter, Andre Bier Johannpeter, J.
      Spencer Lanthier, Arthur Scace and Dr. Michael D. Sopko

      VOTE FOR all the nominees listed above (except for the following nominees
      from whom I withhold my vote):........................................ [ ]
      WITHHOLD VOTE from all nominees [ ] or, if no specification is made, VOTE
      FOR all the nominees listed above in the election of directors;

(b)   APPOINTMENT OF AUDITORS

      VOTE FOR [ ] WITHHOLD VOTE [ ] or, if no specification is made, VOTE FOR
      the appointment of PricewaterhouseCoopers, LLP, Chartered Accountants, as
      auditors of Gerdau Ameristeel and the authorization of the directors to
      fix the auditors' remuneration; and

(c)   APPROVAL OF THE 2005 LONG-TERM INCENTIVE PLAN

      VOTE FOR [ ] WITHHOLD VOTE [ ] or, if no specification is made, VOTE FOR
      the approval of the 2005 Long- Term Incentive Plan of Gerdau Ameristeel;
      and

(d)   OTHER BUSINESS

      Such other business as may properly come before the meeting.

This proxy confers discretionary authority upon the persons named herein as
nominees to vote hereunder with respect, firstly, to the specific matters
identified above where no choice is specified IN WHICH CASE THE SHARES FOR WHICH
THIS PROXY IS GIVEN WILL BE "VOTED" WITH RESPECT TO MATTERS (a), (b) AND (c)
secondly, to all other matters which may properly come before the annual meeting
or any adjournments thereof.

The undersigned hereby revokes any proxy previously given with respect to the
shares represented by this proxy.

Dated: _____________________________________________, 2005.

______________________________________   _______________________________________
Number of Common Shares                  Signature of Shareholder

                                         _______________________________________
                                         Name of Shareholder
                                         (PLEASE PRINT CLEARLY)

NOTES:

(1)   A SHAREHOLDER HAS THE RIGHT TO APPOINT A PERSON TO REPRESENT HIM AT THE
      MEETING OTHER THAN THE MANAGEMENT REPRESENTATIVES DESIGNATED IN THIS
      PROXY. Such right may be exercised by inserting in the space provided the
      name of the other person the shareholder wishes to appoint. Such other
      person need not be a shareholder.

(2)   To be valid, this proxy must be signed and deposited with CIBC Mellon
      Trust Company at 200 Queen's Quay East, Unit 6, Toronto, Ontario, M5A 4K9
      not later than the close of business on May 4, 2005, or, if the meeting is
      adjourned, 48 hours (excluding Saturdays and holidays) before any
      adjourned meeting.

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(3)   If an individual, please sign exactly as your shares are registered.

      If the shareholder is a corporation, this proxy must be executed by a duly
      authorized officer or attorney of the shareholder and, if the corporation
      has a corporate seal, its corporate seal should be affixed

      If shares are registered in the name of an executor, administrator or
      trustee, please sign exactly as the shares are registered. If the shares
      are registered in the name of the deceased or other shareholder, the
      shareholder's name must be printed in the space provided, the proxy must
      be signed by the legal representative with his name printed below his
      signature and evidence of authority to sign on behalf of the shareholder
      must be attached to this proxy.

      In many cases, shares beneficially owned by a holder (a "Non-Registered
      Holder") are registered in the name of a securities dealer or broker or
      other intermediary, or a depository (such as CDS - The Canadian Depository
      for Securities). Non-Registered Holders should, in particular, review the
      section entitled "NON-REGISTERED OWNERS" in the accompanying management
      information circular and carefully follow the instructions of their
      intermediaries.

      All registered holders of shares should refer to the accompanying
      management information circular for further information regarding
      completion and use of this proxy and other information pertaining to the
      meeting.

(4)   If a share is held by two or more persons, any one of them present or
      represented by proxy at a meeting of shareholders may, in the absence of
      the other or others, vote in respect thereof, but if more than one of them
      are present or represented by proxy they shall vote together in respect of
      the share so held.

(5)   If this proxy is not dated in the space provided, it is deemed to bear the
      date on which it is mailed by management of Gerdau Ameristeel.