Exhibit 99.1350CERT

         Certification Pursuant to Section 906 of the Sarbanes Oxley Act

      I, Robert C. Doll, Jr., Chief Executive Officer of Master Enhanced S&P 500
      Series of Quantitative Master Series Trust (the "Fund"), certify that:

            1.    The N-CSR of the Fund (the "Report") fully complies with the
                  requirements of Section 13(a) or 15(d) of the Securities
                  Exchange Act of 1934; and

            2.    The information contained in the Report fairly presents, in
                  all material respects, the financial condition and results of
                  operations of the Fund.

      Dated: February 24, 2005


                                        /s/ Robert C. Doll, Jr.
                                        -----------------------
                                        Robert C. Doll, Jr.,
                                        Chief Executive Officer of
                                        Master Enhanced S&P 500 Series of
                                        Quantitative Master Series Trust

      A signed original of this written statement required by Section 906, or
      other document authenticating, acknowledging, or otherwise adopting the
      signature that appears in typed form within the electronic version of this
      written statement required by Section 906, has been provided to Master
      Enhanced S&P 500 Series of Quantitative Master Series Trust and will be
      retained by Master Enhanced S&P 500 Series of Quantitative Master Series
      Trust and furnished to the Securities and Exchange Commission or its staff
      upon request.



Exhibit 99.1350CERT

         Certification Pursuant to Section 906 of the Sarbanes Oxley Act

      I, Donald C. Burke, Chief Financial Officer of Master Enhanced S&P 500
      Series of Quantitative Master Series Trust (the "Fund"), certify that:

            1.    The N-CSR of the Fund (the "Report") fully complies with the
                  requirements of Section 13(a) or 15(d) of the Securities
                  Exchange Act of 1934; and

            2.    The information contained in the Report fairly presents, in
                  all material respects, the financial condition and results of
                  operations of the Fund.

      Dated: February 24, 2005


                                        /s/ Donald C. Burke
                                        -------------------
                                        Donald C. Burke,
                                        Chief Financial Officer of
                                        Master Enhanced S&P 500 Series of
                                        Quantitative Master Series Trust

      A signed original of this written statement required by Section 906, or
      other document authenticating, acknowledging, or otherwise adopting the
      signature that appears in typed form within the electronic version of this
      written statement required by Section 906, has been provided to Master
      Enhanced S&P 500 Series of Quantitative Master Series Trust and will be
      retained by Master Enhanced S&P 500 Series of Quantitative Master Series
      Trust and furnished to the Securities and Exchange Commission or its staff
      upon request.