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                                                                     EXHIBIT 5.1

                          [BARBER & BARTZ LETTERHEAD]







                                  June 28, 2000




XETA Technologies, Inc.
1814 West Tacoma
Broken Arrow, Oklahoma 74012



Gentlemen:

         We refer to Post-Effective Amendment No. 2 to the Registration
Statement on Form S-8, No. 33-62173 (the "Registration Statement") of XETA
Technologies, Inc., an Oklahoma corporation (the "Company"), to be filed with
the Securities and Exchange Commission on or about June 28, 2000 pursuant to
Rule 416 promulgated under the Securities Act of 1933, as amended (the
"Securities Act"). This Post Effective Amendment No. 2 is being filed for the
purpose of reflecting a change in the amount of securities to be issued under
the XETA Corporation Employee Stock Option Plan and under the individual stock
option agreements identified in the Registration Statement (the Employee Stock
Option Plan and the individual stock option agreements being collectively
referred to herein as the "Plans"), as a result of a two-for-one stock split of
the Common Stock of the Company declared by the Board of Directors on April 7,
2000 for shareholders of record on June 30, 2000 (the "2000 Stock Split").

         We have examined the Company's Restated Certificate of Incorporation,
as amended, the Bylaws as currently in effect, minutes of applicable meetings
and applicable memoranda of action of the Board of Directors and the
shareholders of the Company, and such other corporate records, certificates of
public officials and documents as we have deemed necessary in order to render
the opinions expressed herein.

         Based upon the foregoing, it is our opinion that:

         1. The Company is a corporation duly organized, validly existing and in
good standing under the laws of the State of Oklahoma.

         2. The shares of Common Stock which are issuable on and after the
record date of the 2000 Stock Split pursuant to the terms of the Plans have been
validly authorized for issuance and, upon issuance and delivery thereof and the
payment therefore in accordance with the

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XETA Corporation
June 28, 2000
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provisions of the Plans, the Common Stock so issued will be validly issued,
fully paid and nonassessable.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.

                                                 Very truly yours,

                                                 BARBER & BARTZ

                                                 /s/ NANCY HANANIA JONES
                                                 Nancy Hanania Jones

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