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                                                                     Exhibit 5.1


               2300 MAIN STREET SUITE 1000 KANSAS CITY, MO 64108
                   P.O. BOX 419777 KANSAS CITY, MO 64141.6777
                    TEL: (816) 983-8000  FAX: (816) 983-8080
                            WEBSITE: www.bspmlaw.com



                                  June 5, 2000



BVBC Capital Trust I
Blue Valley Ban Corp
11935 Riley
Overland Park, KS  66225-6128

Ladies and Gentlemen:

         We have acted as counsel to Blue Valley Ban Corp (the "Company") in
connection with the preparation and filing by the Company and BVBC Capital Trust
I (the "Trust") of a registration statement (the "Registration Statement") on
Form S-1 under the Securities Act of 1933, as amended (the "Act"), with respect
to the offer and sale of certain of the Trust's Preferred Securities
(liquidation amount $8 per Preferred Security) (the "Preferred Securities") and
certain of the Company's Junior Subordinated Debentures (the "Debentures") and
the related Preferred Securities Guarantee Agreement by and between the Company
and Wilmington Trust Company, as trustee (the "Guarantee"). 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 the Company in connection with the registration of the
Debentures and the Guarantee. We have examined originals or certified copies of
other documents, including the Registration Statement, as we have deemed
relevant and necessary as a basis for the opinion hereinafter expressed. In such
examination, we have assumed the genuineness of all signatures on original
documents and the authenticity of all documents submitted to us as conformed or
photostatic copies, and the authenticity of the originals of such latter
documents. We have also assumed that when the Debentures are issued and the
Guarantee executed and delivered, the Company will have obtained any required
regulatory approvals. Our opinion is limited to the law of the State of Kansas
and the Federal law of the United States, and we do not express any opinion
herein concerning any other law.

         Based upon and subject to the foregoing, we are of the opinion that,
when issued (with respect to the Debentures), or executed and delivered (with
respect to the Guarantee), as set forth in the Registration Statement, the
Debentures and the Guarantee will be the valid and binding obligations of the
Company, enforceable in accordance with their terms, except as the
enforceability thereof may be limited by bankruptcy, insolvency, moratorium,
reorganization or




            [BLACKWELL SANDERS PEPER MARTIN ADDRESSES LETTERHEAD]
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BVBC Capital Trust I
Blue Valley Ban Corp.
June 5, 2000
Page 2




similar laws relating to or affecting the enforcement of creditors' rights
generally, or by general equity principles, regardless of whether such
enforceability is considered in a proceeding in equity or at law.

         We consent to the references to this opinion and to Blackwell Sanders
Peper Martin LLP in the Prospectus included as part of the Registration
Statement under the caption "Legal Matters," and to the inclusion of this
opinion as an exhibit to the Registration Statement.

                                         Very truly yours,

                                         /s/ Blackwell Sanders Peper Martin LLP