CERTIFICATION PURSUANT TO SECTION 906 OF THE
                            SARBANES-OXLEY ACT

Pursuant to 18 U.S.C. 1350, each of the undersigned, being the Principal
Executive Officer and Principal Financial Officer of AllianceBernstein Mid-Cap
Growth Fund, Inc. (the "Registrant"), hereby certifies that the Registrant's
report on Form N-CSR for the period ended January 31, 2005 (the "Report") fully
complies with the requirements of Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 and that the information contained in the Report fairly
presents, in all material respects, the financial condition and results of
operations of the Registrant.

Date: March 31, 2005

                                   By:  /s/ Marc O. Mayer
                                        -------------------
                                        Marc O. Mayer
                                        President

                                   By:  /s/ Mark D. Gersten
                                        -------------------
                                        Mark D. Gersten
                                        Treasurer and Chief Financial Officer

This certification is being furnished solely pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002 and is not being filed as part of the Report or as a
separate disclosure document.

A signed original of this written statement required by Section 906 has been
provided to the Registrant and will be retained by the Registrant and furnished
to the Securities and Exchange Commission or its staff upon request.