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                                                                    Exhibit 23.3

                         Consent of Independent Auditors

We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Amendment No. 2 to Form S-3) and related Prospectus of
Steel Dynamics, Inc. for the registration of $115,000,000 of 4% Convertible
Subordinated Notes due 2012 and 7,199,024 shares of its common stock, and to the
incorporation by reference therein of our report dated January 24, 2003, (except
for Note 14, as to which the date is March 14, 2003), with respect to the
consolidated financial statements of Steel Dynamics, Inc. included in its Annual
Report (Form 10-K) for the year ended December 31, 2002, filed with the
Securities and Exchange Commission.


                                                           /S/ Ernst & Young LLP

Fort Wayne, Indiana
June 9, 2003


