[Logo] PIONEER Investments(R)





March 5, 2014



VIA ELECTRONIC TRANSMISSION
---------------------------

Securities and Exchange Commission
Division of Investment Management
100 F Street, NE
Washington, DC  20549

Re:     Pioneer Mid Cap Value Fund (the "Fund")
        File Nos. 033-34801 and 811-06106
        CIK No. 0000863334

Ladies and Gentlemen:

Pursuant to Rule 497(j) under the Securities Act of 1933, as amended, I certify
that the forms of prospectus and statement of additional information for the
Fund, which would have been filed under paragraph (c) of Rule 497, do not
differ from those contained in Post-Effective Amendment No. 40 to the Fund's
registration statement on Form N-1A, filed electronically on February 28, 2014
(Accession No. 0000869356-14-000005).

If you have any questions concerning the foregoing certification, please
contact me at (617) 422-4703.

Very truly yours,



/s/ Eugenio Martinez
-------------------------
    Eugenio Martinez
    Legal Product Manager


cc:     Christopher J. Kelley, Esq.
        Toby R. Serkin, Esq.



Pioneer Investment Management, Inc.
60 State Street
Boston, MA  02109-1820




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