EXHIBIT 32.2
CERTIFICATION PURSUANT TO
18 U.S.C. §1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
In connection with the Annual Report of Natural Gas Services Group, Inc. (the “Company”) on Form 10-K for the year ended December 31, 2007, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Earl R. Wait, Vice President - Accounting (Principal Accounting Officer) of the Company, certify, pursuant to 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:
| 1. | The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and |
| 2. | The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. |
| Date: March 7, 2008 | Natural Gas Services Group, Inc. | ||
| By: | /s/ Earl R. Wait | ||
| Earl R. Wait | |||
| Vice President of Accounting (Principal Accounting Officer) and Treasurer |