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                                                                 Exhibit 5.1

                 [KRONISH LIEB WEINER & HELLMAN LLP LETTERHEAD]

                                  April 8, 2003


BHA Group Holdings, Inc.
8800 East 63rd Street
Kansas City, Missouri, 64133

Gentlemen:

         We have acted as counsel for BHA Group Holdings, Inc., a Delaware
corporation (the "Company"), in connection with the registration, pursuant to a
Registration Statement on Form S-8 (the "Registration Statement") by the Company
under the Securities Act of 1933, as amended (the "Act"), of 500,000 shares of
the Company's common stock, par value $.01 per share (the "Common Stock"), to be
offered for sale by the Company from time to time under the Company's Amended
and Restated Incentive Stock Plan adopted in September 2001 (the "Plan").

         We have examined the Company's Certificate of Incorporation and Bylaws,
as amended, and minute books and such other documents and records as we have
deemed necessary and relevant as a basis for our opinions hereinafter set forth.
For the purposes of this letter, we have assumed the genuineness of all
signatures and the conformity to original documents of all instruments furnished
to us for review or examination as copies.

         Based on the foregoing and having regard to such legal considerations
as we have deemed relevant, it is our opinion that:

         1. The Company is a corporation duly organized under the laws of the
State of Delaware.

         2. The Common Stock covered by the Registration Statement that may be
issued under the Plan has been validly authorized.

         3. When (i) the Common Stock has been duly registered under the Act,
(ii) certificates for the Common Stock have been duly delivered, and (iii) the
Company has received the consideration to be received by it pursuant to and upon
exercise of the related options awarded under the Plan, the Common Stock will be
validly issued, fully paid and non-assessable.

         We hereby consent to the inclusion of this opinion in the Registration
Statement and to the references to this firm contained therein.

                                       Very truly yours,

                                       /s/ Kronish Lieb Weiner & Hellman LLP

                                       KRONISH LIEB WEINER & HELLMAN LLP


