The purpose of this research is to investigate the factors affecting Iran’s tourism industry with a sustainable development approach. The statistical population in the qualitative research includes experts and specialists in the tourism organization and professors with proficiency in the field of tourism, and the quantitative research comprises the experts of tourism development in the tourism organizations of Iran. The sampling methods in the qualitative and quantitative studies are purposeful and random stratified, respectively. The method of data collection in this research is based on library studies, a review of relevant texts and literature, and field-based and data collection is performed through interviews and questionnaires. Non-probability purposive sampling was applied to select the interviewees, and during this process, experts were tried to have practical experience in addition to theoretical knowledge. The results of the research demonstrate that based on the Dalala technique, the institutional criterion is the most effective and the sustainable human resources index has a very high level of effectiveness, and the criteria of sustainable human resources have the most interactions with other criteria studied. Furthermore, based on the structural equation technique, it was determined that all the identified factors have a significant impact on the development of the tourism industry.
