Quality Auditing is a systematic, independent and documented process for obtaining audit evidence and evaluating it objectively to determine the extent to which audit criteria are fulfilled. The purpose of this paper is to find out the impact of ISO 9001 certification audit on oil and gas companies' performance in Qatar. More than 100 oil and gas companies have been certified ISO 9001. Therefore, it is necessary to study and analyze the impact of that certification on their performance. Survey study has been done by distributing a questionnaire by e-mail or by handing it personally to most of the certified oil and gas companies in Qatar. The response rate was 33.6% of surveyed companies. The statistical operations with the results of analytical study have been done to achieve the goal and objectives of the research. Finally, ISO 9001 certification audit is found to have a positive effect on oil and gas companies' performance in Qatar.