<PAGE>   1
  As filed with the Securities and Exchange Commission on February 16, 2001

                                                   REGISTRATION NO. 333-________


                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933


                              STEEL DYNAMICS, INC.
    (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS ARTICLES OF INCORPORATION)



     Indiana                         3312                      35-1929476

(State or other          (Primary standard industrial         (IRS Employer
jurisdiction of           classification code number)        Identification No.)
incorporation)



                      6714 POINTE INVERNESS WAY, SUITE 200
                            FORT WAYNE, INDIANA 46804
                                 (219) 459-3553

               (Address, including zip code and telephone number,
                  including area code of Registrant's principal
                               executive offices)

       AMENDED AND RESTATED OFFICER AND MANAGER CASH AND STOCK BONUS PLAN


                                 KEITH E. BUSSE
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                              STEEL DYNAMICS, INC.
                      6714 POINTE INVERNESS WAY, SUITE 200
                            FORT WAYNE, INDIANA 46804
                                 (219) 459-3553

                (NAME, ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE
               NUMBER, INCLUDING AREA CODE, OF AGENT FOR SERVICE)

                                    COPY TO:
                             ROBERT S. WALTERS, ESQ.
                                BARRETT & MCNAGNY
                              215 EAST BERRY STREET
                            FORT WAYNE, INDIANA 46802
                                 (219) 423-9551


                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>

                                   NUMBER OF        PROPOSED MAXIMUM       PROPOSED MAXIMUM        AMOUNT OF
  TITLE OF EACH CLASS OF         SHARES TO BE      OFFERING PRICE PER     AGGREGATE OFFERING     REGISTRATION
SECURITIES TO BE REGISTERED       REGISTERED            SHARE(1)                 PRICE                FEE
---------------------------       ----------            --------                 -----                ---

<S>                              <C>               <C>                    <C>                    <C>
Common Stock, $0.01 par value      450,000             Variable               $5,484,375           $1,371.09


</TABLE>

      (1) Estimated Pursuant to Rule 457(h) and Rule 457(c) solely for the
purpose of calculating the registration fee, on the basis of the last trade of
$12.1875 for the Common Stock as reported on the NASDAQ National Market System
on February 13, 2001.
<PAGE>   2
                                     PART I
              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

      The documents containing the information specified in Part I will be sent
or given to employees/distributees as specified in Rule 428(b)(1) and, together
with the documents incorporated by reference in this Registration Statement
pursuant to Item 3 of Part II of this Form S-8, taken together, shall be
intended to constitute a Prospectus that meets the requirements of Section 10(a)
of the Securities Act. The foregoing documents are not required to be filed and
are not being filed with the Commission either as part of this Registration
Statement or as prospectuses or prospectus supplements pursuant to Rule 424.

                                     PART II
               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

      The following documents, which have been filed by Steel Dynamics, Inc.
(the "Company" or the "Registrant") with the Securities and Exchange Commission
(the "Commission"), are incorporated herein by reference:

      (a) The Company's Form 10-K Annual Report for its fiscal year ended
          December 31, 1999, filed March 29, 2000.

      (b) The Company's Form 10-Q Quarterly Report for its fiscal quarter ended
          March 31, 2000, filed May 4, 2000.

      (c) The Company's Form 10-Q Quarterly Report for its fiscal quarter ended
          June 30, 2000, filed August 11, 2000.

      (d) The Company's Form 10-Q Quarterly Report for its fiscal quarter ended
          September 30, 2000, filed November 13, 2000.

      (e) All other reports filed pursuant to Section 13(a) or 15(d) of the
          Securities Exchange Act of 1934 since December 31, 2000, the end of
          the Company's fiscal year.

      (f) The Company's Amended and Restated Officer and Manager Cash and Stock
          Bonus Plan, attached as Exhibit 10.23a to this Form S-8 Registration
          Statement.

      All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, prior to the
filing of a post-effective amendment to this Form S-8, which indicates that all
securities offered pursuant to the Company's Amended and Restated Officer and
Manager Cash and Stock Bonus Plan have been distributed or which de-registers
all securities then remaining undistributed, shall be deemed to be incorporated
herein by reference and shall be deemed to be a part hereof, from the date of
filing of such documents.

      Any statement contained in a document incorporated by reference herein or
in an exhibit hereto shall be deemed to be modified or superseded for purposes
hereof to the extent that a statement contained herein (or in any other
subsequently filed document which is also incorporated by reference herein)
modifies or supersedes such statement. Any statement so modified or superseded
shall not be deemed to constitute a part hereof except as so modified or
superseded.

ITEM 4.  DESCRIPTION OF SECURITIES.

      Not Applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not Applicable.



                                       2
<PAGE>   3
ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      The Company's Amended and Restated Articles of Incorporation (the
"Articles") limit the liability of directors and officers by providing that the
Company shall indemnify a person made a party to a proceeding, because that
person is or was a director or officer, against liability incurred in the
proceeding, as well as expenses (including counsel fees), if the person's
conduct was in good faith, and if he or she reasonably believed, in the case of
"official conduct" with the Company, that his or her conduct was in the
Company's best interests (or at least that the conduct was not opposed to the
Company's best interests), and, in the case of any criminal proceeding, that the
individual either had reasonable cause to believe that the conduct was lawful,
or had no reasonable cause to believe that the conduct was unlawful.
Indemnification against reasonable expenses incurred by a director or officer is
also required in any case in which that person, having been made a party to a
proceeding because he or she was a director or officer, has been wholly
successful, on the merits or otherwise, in the defense of such action. These
provisions prohibit indemnity if a director or officer is found liable in a
proceeding by the Company (or in a stockholder derivative action on behalf of
the Company) against the director or officer, or in connection with a proceeding
in which the director or officer has been adjudged liable for having improperly
received a personal benefit in his or her capacity as a director.

      A director's conduct with respect to an employee benefit plan, for a
purpose the director reasonably believed to be in the interests of the
participants in and beneficiaries of the plan, is conduct which complies with
the indemnification standard set forth in the Articles.

      An indemnification determination may be made by the Company's Board of
Directors by majority vote of a quorum consisting of directors not at the time
parties to the proceeding, or, if such a quorum cannot be obtained, by majority
vote of a committee duly designated by the Board of Directors (in which
deliberations the interested directors may participate) consisting solely of two
or more directors not at the time parties to the proceeding, or by a
determination by special legal counsel engaged by the Board of Directors.
Shareholders, by majority vote (excluding shares owned by or voted under the
control of directors who are at the time parties to the proceeding) may also
order indemnification, as well as a court, upon application by the director or
officer seeking indemnification, if the court determines that the director or
officer is fairly and reasonably entitled to indemnification in view of all of
the relevant circumstances (whether or not that person met the other standards
set forth in the Articles). The Articles state that it is intended that
indemnification be granted to the full extent permissible under the law, except
for matters as to which indemnification would be in contravention of the laws of
the State of Indiana or the United States of America, whether as a matter of
public policy or pursuant to any statutory provision. The underlying statutory
standard for director liability in Indiana is broad, providing that a director
is not liable for any action taken as a director, or any failure to take any
action, unless the director has breached or failed to perform the duties of the
director's office, and the breach or failure to perform constitutes willful
misconduct or recklessness.

      The Company maintains officers' and directors' liability insurance which
insures, subject to policy limits and retention amounts, against liabilities
that officers and directors of the Company may incur in their respective
capacities.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

      Not Applicable.

ITEM 8.  EXHIBITS.

      See Index to Exhibits on page 7 of this Registration Statement.

ITEM 9.  UNDERTAKINGS.

      (a)  The undersigned Registrant hereby undertakes:




                                       3
<PAGE>   4
           (1)  To file, during any period in which offers or sales are being
                made, a post-effective amendment to this Registration Statement:

                  (i)   To include any prospectus required by Section 10(a)(3)
                        of the Securities Act of 1933; and

                  (ii)  To reflect in the Prospectus any facts or events arising
                        after the effective date of the Registration Statement
                        (or the most recent post-effective amendment thereof)
                        which, individually or in the aggregate, represent a
                        fundamental change in the information set forth in the
                        Registration Statement;

                  (iii) To include any material information with respect to the
                        plan of distribution not previously disclosed in the
                        Registration Statement or any material change to such
                        information in the Registration Statement; provided,
                        however, that clauses (i) and (ii) do not apply if the
                        Registration Statement is on Form S-3, Form S-8, or Form
                        F-3, and the information required to be included in a
                        post-effective amendment by those clauses is contained
                        in periodic reports filed with or furnished to the
                        Commission by the Registrant pursuant to Section 13 or
                        Section 15(d) of the Securities Exchange Act of 1934
                        that are incorporated by reference in the Registration
                        Statement.

           (2)  That, for the purpose of determining any liability under the
                Securities Act of 1933, each such post-effective amendment shall
                be deemed to be a new registration statement relating to the
                securities distributed in connection therewith, and the
                distribution of such securities shall be deemed to be the
                initial bona fide offering thereof.

           (3)  To remove from registration by means of a post-effective
                amendment any of the securities being registered which remain
                unsold at the termination of the offering.

      (b)  The undersigned Registrant hereby undertakes that, for purposes of
           determining any liabilities under the Securities Act of 1933, each
           filing of the Registrant's annual report pursuant to Section 13(a) or
           Section 15(d) of the Securities Exchange Act of 1934 (and, where
           applicable, each filing of an employee benefit plan's annual report
           pursuant to Section 15(d) of the Securities Exchange Act of 1934)
           that is incorporated by reference in the Registration Statement shall
           be deemed to be a new registration statement relating to the
           securities offered therein, and the offering of such securities at
           that time shall be deemed to be the initial bona fide offering
           thereof.

      (c)  Insofar as indemnification for liabilities arising under the
           Securities Act of 1933 may be permitted to directors or officers of
           the Company pursuant to the Articles, or otherwise, the Company has
           been informed that in the opinion of the Securities and Exchange
           Commission such indemnification is against public policy as expressed
           in the Securities Act and is therefore unenforceable. In the event
           that a claim for indemnification against such liabilities (other than
           the payment by the Company of expenses incurred or paid by a director
           or officer in a successful defense of any action, suit or proceeding)
           is asserted by such director or officer in connection with the
           securities being registered hereunder, the Company will, unless in
           the opinion of its counsel the question has already been settled by
           controlling precedent, submit to a court of appropriate jurisdiction
           the question whether such indemnification by it is against public
           policy as expressed in the Securities Act and will be governed by the
           final adjudication of such issue.



                                       4
<PAGE>   5
                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the city of Fort Wayne, Indiana, on the 15th day of February,
2001.




                                     STEEL DYNAMICS, INC.


                                     By: /s/ Keith E. Busse
                                        ----------------------------------
                                     Keith E. Busse
                                     President and Chief Executive Officer




      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the date indicated:




Date:  February 15, 2001                 /s/ Keith E. Busse
                                         -------------------------------------
                                         Keith E. Busse, President and Chief
                                         Executive Officer and Director
                                         (Principal Executive Officer)

Date:  February 15, 2001                 /s/ Tracy L. Shellabarger
                                         -------------------------------------
                                         Tracy L. Shellabarger, Vice President
                                         and Chief Financial Officer and
                                         Director (Principal Financial and
                                         Accounting Officer)

Date:  February 15, 2001                 /s/ Mark D. Millett
                                         -------------------------------------
                                         Mark D. Millett, Vice President and
                                         Director

Date:  February 15, 2001                 /s/ Richard P. Teets
                                         -------------------------------------
                                         Richard P. Teets, Jr., Vice President
                                         and Director

Date:  February 15, 2001                 /s/ John C. Bates
                                         -------------------------------------
                                         John C. Bates, Director




                                       5
<PAGE>   6
Date:  February 15, 2001                 /s/ Leonard Rifkin
                                         -------------------------------------
                                         Leonard Rifkin, Director

Date:  February 15, 2001                 /s/ Jurgen Kolb
                                         -------------------------------------
                                         Jurgen Kolb, Director

Date:  February 15, 2001                 /s/ Joseph D. Ruffolo
                                         -------------------------------------
                                         Joseph D. Ruffolo, Director

Date:  February __, 2001
                                         -------------------------------------
                                         Kazuhiro Atsushi, Director

Date:  February __, 2001
                                         -------------------------------------
                                         Richard J. Freeland, Director

Date:  February 15, 2001                 /s/ James E. Kelley
                                         -------------------------------------
                                         James E. Kelley, Director




                                       6
<PAGE>   7
                               INDEX TO EXHIBITS


      Exhibit Number*      Description of Document

           5.1             Opinion of Barrett & McNagny

           10.23a          Steel Dynamics, Inc. Amended and Restated Officer and
                           Manager Cash and Stock Bonus Plan

           23.1a           Consent of Ernst & Young LLP

           23.1b           Consent of Deloitte & Touche  LLP


*     All other exhibits, as set forth in the Index to Exhibits attached to the
      Company's 1999 Form 10-K, filed with the Commission on March 29, 2000, are
      hereby incorporated by reference.



                                       7
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{"company-data": {"conformed-name": "STEEL DYNAMICS INC", "cik": "0001022671", "assigned-sic": "3312", "irs-number": "351929476", "state-of-incorporation": "IN", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-55888", "film-number": "1550115"}, "business-address": {"street1": "7030 POINTE INVERNESS WAY", "street2": "SUITE 310", "city": "FORT WAYNE", "state": "IN", "zip": "46804", "phone": "2194593553"}, "mail-address": {"street1": "7030 POINTE INVERNERSS WAY", "street2": "SUITE 310", "city": "FORT WAYNE", "state": "IN", "zip": "46804"}}
1
  As filed with the Securities and Exchange Commission on February 16, 2001

                                                   REGISTRATION NO. 333-________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                              STEEL DYNAMICS, INC.
    (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS ARTICLES OF INCORPORATION)

     Indiana                         3312                      35-1929476

(State or other          (Primary standard industrial         (IRS Employer
jurisdiction of           classification code number)        Identification No.)
incorporation)

                      6714 POINTE INVERNESS WAY, SUITE 200
                            FORT WAYNE, INDIANA 46804
                                 (219) 459-3553

               (Address, including zip code and telephone number,
                  including area code of Registrant's principal
                               executive offices)

       AMENDED AND RESTATED OFFICER AND MANAGER CASH AND STOCK BONUS PLAN

                                 KEITH E. BUSSE
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                              STEEL DYNAMICS, INC.
                      6714 POINTE INVERNESS WAY, SUITE 200
                            FORT WAYNE, INDIANA 46804
                                 (219) 459-3553

                (NAME, ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE
               NUMBER, INCLUDING AREA CODE, OF AGENT FOR SERVICE)

                                    COPY TO:
                             ROBERT S. WALTERS, ESQ.
                                BARRETT & MCNAGNY
                              215 EAST BERRY STREET
                            FORT WAYNE, INDIANA 46802
                                 (219) 423-9551

                         CALCULATION OF REGISTRATION FEE
NUMBER OF        PROPOSED MAXIMUM       PROPOSED MAXIMUM        AMOUNT OF
  TITLE OF EACH CLASS OF         SHARES TO BE      OFFERING PRICE PER     AGGREGATE OFFERING     REGISTRATION
SECURITIES TO BE REGISTERED       REGISTERED            SHARE(1)                 PRICE                FEE
---------------------------       ----------            --------                 -----                ---
Common Stock, $0.01 par value      450,000             Variable               $5,484,375           $1,371.09
(1) Estimated Pursuant to Rule 457(h) and Rule 457(c) solely for the
purpose of calculating the registration fee, on the basis of the last trade of
$12.1875 for the Common Stock as reported on the NASDAQ National Market System
on February 13, 2001.
2
                                     PART I
              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

      The documents containing the information specified in Part I will be sent
or given to employees/distributees as specified in Rule 428(b)(1) and, together
with the documents incorporated by reference in this Registration Statement
pursuant to Item 3 of Part II of this Form S-8, taken together, shall be
intended to constitute a Prospectus that meets the requirements of Section 10(a)
of the Securities Act. The foregoing documents are not required to be filed and
are not being filed with the Commission either as part of this Registration
Statement or as prospectuses or prospectus supplements pursuant to Rule 424.

                                     PART II
               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

      The following documents, which have been filed by Steel Dynamics, Inc.
(the "Company" or the "Registrant") with the Securities and Exchange Commission
(the "Commission"), are incorporated herein by reference:

      (a) The Company's Form 10-K Annual Report for its fiscal year ended
          December 31, 1999, filed March 29, 2000.

      (b) The Company's Form 10-Q Quarterly Report for its fiscal quarter ended
          March 31, 2000, filed May 4, 2000.

      (c) The Company's Form 10-Q Quarterly Report for its fiscal quarter ended
          June 30, 2000, filed August 11, 2000.

      (d) The Company's Form 10-Q Quarterly Report for its fiscal quarter ended
          September 30, 2000, filed November 13, 2000.

      (e) All other reports filed pursuant to Section 13(a) or 15(d) of the
          Securities Exchange Act of 1934 since December 31, 2000, the end of
          the Company's fiscal year.

      (f) The Company's Amended and Restated Officer and Manager Cash and Stock
          Bonus Plan, attached as Exhibit 10.23a to this Form S-8 Registration
          Statement.

      All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, prior to the
filing of a post-effective amendment to this Form S-8, which indicates that all
securities offered pursuant to the Company's Amended and Restated Officer and
Manager Cash and Stock Bonus Plan have been distributed or which de-registers
all securities then remaining undistributed, shall be deemed to be incorporated
herein by reference and shall be deemed to be a part hereof, from the date of
filing of such documents.

      Any statement contained in a document incorporated by reference herein or
in an exhibit hereto shall be deemed to be modified or superseded for purposes
hereof to the extent that a statement contained herein (or in any other
subsequently filed document which is also incorporated by reference herein)
modifies or supersedes such statement. Any statement so modified or superseded
shall not be deemed to constitute a part hereof except as so modified or
superseded.

ITEM 4.  DESCRIPTION OF SECURITIES.

      Not Applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not Applicable.

                                       2
3
ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      The Company's Amended and Restated Articles of Incorporation (the
"Articles") limit the liability of directors and officers by providing that the
Company shall indemnify a person made a party to a proceeding, because that
person is or was a director or officer, against liability incurred in the
proceeding, as well as expenses (including counsel fees), if the person's
conduct was in good faith, and if he or she reasonably believed, in the case of
"official conduct" with the Company, that his or her conduct was in the
Company's best interests (or at least that the conduct was not opposed to the
Company's best interests), and, in the case of any criminal proceeding, that the
individual either had reasonable cause to believe that the conduct was lawful,
or had no reasonable cause to believe that the conduct was unlawful.
Indemnification against reasonable expenses incurred by a director or officer is
also required in any case in which that person, having been made a party to a
proceeding because he or she was a director or officer, has been wholly
successful, on the merits or otherwise, in the defense of such action. These
provisions prohibit indemnity if a director or officer is found liable in a
proceeding by the Company (or in a stockholder derivative action on behalf of
the Company) against the director or officer, or in connection with a proceeding
in which the director or officer has been adjudged liable for having improperly
received a personal benefit in his or her capacity as a director.

      A director's conduct with respect to an employee benefit plan, for a
purpose the director reasonably believed to be in the interests of the
participants in and beneficiaries of the plan, is conduct which complies with
the indemnification standard set forth in the Articles.

      An indemnification determination may be made by the Company's Board of
Directors by majority vote of a quorum consisting of directors not at the time
parties to the proceeding, or, if such a quorum cannot be obtained, by majority
vote of a committee duly designated by the Board of Directors (in which
deliberations the interested directors may participate) consisting solely of two
or more directors not at the time parties to the proceeding, or by a
determination by special legal counsel engaged by the Board of Directors.
Shareholders, by majority vote (excluding shares owned by or voted under the
control of directors who are at the time parties to the proceeding) may also
order indemnification, as well as a court, upon application by the director or
officer seeking indemnification, if the court determines that the director or
officer is fairly and reasonably entitled to indemnification in view of all of
the relevant circumstances (whether or not that person met the other standards
set forth in the Articles). The Articles state that it is intended that
indemnification be granted to the full extent permissible under the law, except
for matters as to which indemnification would be in contravention of the laws of
the State of Indiana or the United States of America, whether as a matter of
public policy or pursuant to any statutory provision. The underlying statutory
standard for director liability in Indiana is broad, providing that a director
is not liable for any action taken as a director, or any failure to take any
action, unless the director has breached or failed to perform the duties of the
director's office, and the breach or failure to perform constitutes willful
misconduct or recklessness.

      The Company maintains officers' and directors' liability insurance which
insures, subject to policy limits and retention amounts, against liabilities
that officers and directors of the Company may incur in their respective
capacities.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

      Not Applicable.

ITEM 8.  EXHIBITS.

      See Index to Exhibits on page 7 of this Registration Statement.

ITEM 9.  UNDERTAKINGS.

      (a)  The undersigned Registrant hereby undertakes:

                                       3
4
           (1)  To file, during any period in which offers or sales are being
                made, a post-effective amendment to this Registration Statement:

                  (i)   To include any prospectus required by Section 10(a)(3)
                        of the Securities Act of 1933; and

                  (ii)  To reflect in the Prospectus any facts or events arising
                        after the effective date of the Registration Statement
                        (or the most recent post-effective amendment thereof)
                        which, individually or in the aggregate, represent a
                        fundamental change in the information set forth in the
                        Registration Statement;

                  (iii) To include any material information with respect to the
                        plan of distribution not previously disclosed in the
                        Registration Statement or any material change to such
                        information in the Registration Statement; provided,
                        however, that clauses (i) and (ii) do not apply if the
                        Registration Statement is on Form S-3, Form S-8, or Form
                        F-3, and the information required to be included in a
                        post-effective amendment by those clauses is contained
                        in periodic reports filed with or furnished to the
                        Commission by the Registrant pursuant to Section 13 or
                        Section 15(d) of the Securities Exchange Act of 1934
                        that are incorporated by reference in the Registration
                        Statement.

           (2)  That, for the purpose of determining any liability under the
                Securities Act of 1933, each such post-effective amendment shall
                be deemed to be a new registration statement relating to the
                securities distributed in connection therewith, and the
                distribution of such securities shall be deemed to be the
                initial bona fide offering thereof.

           (3)  To remove from registration by means of a post-effective
                amendment any of the securities being registered which remain
                unsold at the termination of the offering.

      (b)  The undersigned Registrant hereby undertakes that, for purposes of
           determining any liabilities under the Securities Act of 1933, each
           filing of the Registrant's annual report pursuant to Section 13(a) or
           Section 15(d) of the Securities Exchange Act of 1934 (and, where
           applicable, each filing of an employee benefit plan's annual report
           pursuant to Section 15(d) of the Securities Exchange Act of 1934)
           that is incorporated by reference in the Registration Statement shall
           be deemed to be a new registration statement relating to the
           securities offered therein, and the offering of such securities at
           that time shall be deemed to be the initial bona fide offering
           thereof.

      (c)  Insofar as indemnification for liabilities arising under the
           Securities Act of 1933 may be permitted to directors or officers of
           the Company pursuant to the Articles, or otherwise, the Company has
           been informed that in the opinion of the Securities and Exchange
           Commission such indemnification is against public policy as expressed
           in the Securities Act and is therefore unenforceable. In the event
           that a claim for indemnification against such liabilities (other than
           the payment by the Company of expenses incurred or paid by a director
           or officer in a successful defense of any action, suit or proceeding)
           is asserted by such director or officer in connection with the
           securities being registered hereunder, the Company will, unless in
           the opinion of its counsel the question has already been settled by
           controlling precedent, submit to a court of appropriate jurisdiction
           the question whether such indemnification by it is against public
           policy as expressed in the Securities Act and will be governed by the
           final adjudication of such issue.

                                       4
5
                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the city of Fort Wayne, Indiana, on the 15th day of February,
2001.

                                     STEEL DYNAMICS, INC.

                                     By: /s/ Keith E. Busse
                                        ----------------------------------
                                     Keith E. Busse
                                     President and Chief Executive Officer

      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the date indicated:

Date:  February 15, 2001                 /s/ Keith E. Busse
                                         -------------------------------------
                                         Keith E. Busse, President and Chief
                                         Executive Officer and Director
                                         (Principal Executive Officer)

Date:  February 15, 2001                 /s/ Tracy L. Shellabarger
                                         -------------------------------------
                                         Tracy L. Shellabarger, Vice President
                                         and Chief Financial Officer and
                                         Director (Principal Financial and
                                         Accounting Officer)

Date:  February 15, 2001                 /s/ Mark D. Millett
                                         -------------------------------------
                                         Mark D. Millett, Vice President and
                                         Director

Date:  February 15, 2001                 /s/ Richard P. Teets
                                         -------------------------------------
                                         Richard P. Teets, Jr., Vice President
                                         and Director

Date:  February 15, 2001                 /s/ John C. Bates
                                         -------------------------------------
                                         John C. Bates, Director

                                       5
6
Date:  February 15, 2001                 /s/ Leonard Rifkin
                                         -------------------------------------
                                         Leonard Rifkin, Director

Date:  February 15, 2001                 /s/ Jurgen Kolb
                                         -------------------------------------
                                         Jurgen Kolb, Director

Date:  February 15, 2001                 /s/ Joseph D. Ruffolo
                                         -------------------------------------
                                         Joseph D. Ruffolo, Director

Date:  February __, 2001
                                         -------------------------------------
                                         Kazuhiro Atsushi, Director

Date:  February __, 2001
                                         -------------------------------------
                                         Richard J. Freeland, Director

Date:  February 15, 2001                 /s/ James E. Kelley
                                         -------------------------------------
                                         James E. Kelley, Director

                                       6
7
                               INDEX TO EXHIBITS

      Exhibit Number*      Description of Document

           5.1             Opinion of Barrett & McNagny

           10.23a          Steel Dynamics, Inc. Amended and Restated Officer and
                           Manager Cash and Stock Bonus Plan

           23.1a           Consent of Ernst & Young LLP

           23.1b           Consent of Deloitte & Touche  LLP

*     All other exhibits, as set forth in the Index to Exhibits attached to the
      Company's 1999 Form 10-K, filed with the Commission on March 29, 2000, are
      hereby incorporated by reference.

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