Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm


We consent to the references to our firm under the captions "Financial
Highlights" in the Class A, Class B, Class C, Class R, and Class Y Shares'
Prospectus and "Independent Registered Public Accounting Firm" and "Financial
Statements" in the Class A, Class B, Class C, Class R, and Class Y Shares'
Statement of Additional Information and to the incorporation by reference of our
report, dated December 28, 2010, on the financial statements and financial
highlights of Pioneer Mid Cap Value Fund included in the Annual Report to the
Board of Trustees and Shareowners for the year ended October 31, 2010 as filed
with the Securities and Exchange Commission in Post-Effective Amendment Number
34 to the Registration Statement (Form N-1A, No. 333-34801) of Pioneer Mid Cap
Value Fund.



/s/ ERNST & YOUNG LLP

Boston, Massachusetts
March 16, 2011