Exhibit 5.1



                                  May 23, 2005

Atlas Pipeline Partners, L.P.
311 Rouser Road
Moon Township, PA 15108

Ladies and Gentlemen:

         We have acted as counsel to Atlas Pipeline Partners, L.P., a Delaware
limited partnership ("Atlas"), Atlas Pipeline Operating Partnership, L.P., a
Delaware limited partnership, Atlas Pipeline New York, LLC, a Pennsylvania
limited liability company, Atlas Pipeline Ohio, LLC, a Pennsylvania limited
liability company, and Atlas Pipeline Pennsylvania, LLC, a Pennsylvania limited
liability company, in connection with the preparation and filing by these
entities of a registration statement on Form S-3 under the Securities Act of
1933, as amended, File No. 333-113523 (the "Registration Statement"), the
Prospectus included therein dated April 5, 2004 (the "Prospectus"), and the
Preliminary Prospectus Supplement of even date herewith (the "Preliminary
Prospectus Supplement") with respect to the offer and sale by Atlas of up to
2,545,000 common units of limited partnership interest of Atlas (the "Common
Units"). In connection therewith, you have requested our opinion as to certain
matters referred to below.

         In our capacity as such counsel, we have familiarized ourselves with
the actions taken by Atlas in connection with the registration of the Common
Units. We have examined the originals or certified copies of such records,
agreements, certificates of public officials and others, and such other
documents, including the Registration Statement, the Prospectus and the
Preliminary Prospectus Supplement, as we have deemed relevant and necessary as a
basis for the opinions hereinafter expressed.

         Based upon and subject to the foregoing, we are of the opinion that:

         1. Atlas is a limited partnership which has been duly formed, is
validly existing and is in good standing under the Delaware Revised Uniform
Limited Partnership Act.

         2. When sold as set forth in the Registration Statement, the Prospectus
and the Preliminary Prospectus Supplement, the Common Units will be validly
issued, fully paid and non-assessable, except as such nonassessment may be
affected by the matters described in the Prospectus under the caption "Our
Partnership Agreement--Limited Liability."

         The opinion expressed herein is limited to the Delaware Revised Uniform
Limited Partnership Act, as currently in effect.

         We consent to the reference to this opinion and to Ledgewood in the
Prospectus and Preliminary Prospectus Supplement, and to the inclusion of this
opinion as an exhibit to the Registration Statement.


                                                     Very truly yours,

                                                     /s/ Ledgewood

                                                     LEDGEWOOD