Given the fluctuations of oil price in international markets and its effect on global economy, it is expected that gas industry and use of gas as an alternative energy, have become more important. Therefore, identification of strategic decisions in this industry has attracted increasing attention of managers and researchers. This study aims to identify and evaluate strategic decisions in the National Iranian Gas Company, using DEMATEL method for the first time. For data collection, paired comparison questionnaire have been used. The results of the research show that expanding operations to enter a new market, opening and starting up a new plant or facility, expansion of capacity and restructuring are respectively the most important strategic decisions in the industry.