Washington, D.C.

                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

         Date of Report (Date of earliest event reported): July 13, 2004

                                   AAON, INC.
             (Exact name of registrant as specified in its charter)

           Nevada                       0-18953                  87-0448736
           ------                       -------                  ----------
(State or other jurisdiction          (Commission               (IRS Employer
      of incorporation)               File Number)           Identification No.)

                     2425 South Yukon, Tulsa, Oklahoma 74107
                    (Address of principal executive offices)

       Registrant's telephone number, including area code: (918) 583-2266

Item 12.  Results of Operations and Financial Condition.

          On July 13, 2004, Registrant issued a press release concerning its
     results of operations for the three months ended and at June 30, 2004. A
     copy of such press release is attached as Exhibit "A" hereto.


     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                             AAON, INC.

Date:  July 15, 2004                         By: /s/ John B. Johnson, Jr.
                                                 John B. Johnson, Jr., Secretary

                                   EXHIBIT "A"

July 13, 2004

                                   AAON, Inc.
                  2425 South Yukon Ave. o Tulsa, OK 74107-2728
                   o Ph: (918) 583-2266 o Fax: (918) 583-6094 o
                            For Further Information:
          Jerry R. Levine o Phone: (914) 244-0292 o Fax: (914) 244-0295

                          AAON FORESEES SECOND QUARTER
                         RECORD SALES AND LOWER EARNINGS

Tulsa, OK, July 13, 2004 - AAON, Inc. (NASDAQ-AAON) today announced that it
expects to report record sales for the second quarter ended June 30, 2004, while
net income will be substantially less than the first quarter of 2004. The higher
sales are attributable to a record backlog and some contribution of revenues
from AAON Canada, Inc., acquired on May 5, 2004, despite closings of the
Company's Tulsa plant for four days during the period due to computer and
electrical outages. The lower earnings resulted from the continued impact of
higher steel and copper prices and startup costs associated with a new coil
project, a loss incurred by AAON Canada, Inc., equipment failures at the
Company's Longview, Texas plant, which prevented coil production needed by the
Tulsa facility, and the above-referenced plant closings.

This press release contains "forward-looking statements" within the meaning of
Section 27A of the Securities Act of 1933. Statements regarding future prospects
and developments are based upon current expectations and involve certain risks
and uncertainties that could cause actual results and developments to differ
materially from the forward-looking statements.