The existence of geological diversity is the most important basis for the development of geotourism and the identification of geological heritage for the establishment of geoparks. Geotourism activities focus on geological tourism activities and is a branch of tourism that focuses on inanimate nature tourism and is a type of sustainable and educational tourism (with the benefit of the local community). In fact, geotourism is a knowledge-oriented tourism that comes from the interdisciplinary integration of the tourism industry with the preservation and interpretation of inanimate nature attractions (along with the cultural issues related to them) and presenting it to the general public in the form of a geosite. Geotourism, despite being a global phenomenon, is also a relatively new concept. The purpose of this research is to evaluate the geotourism potential of the geological heritage of Maragheh city using the GAM geosite evaluation method (based on experts' opinion). The current research is descriptive-analytical and practical in terms of purpose. The results were the identification of 11 geosites, and a survey of the geosites was conducted with the opinions of 20 experts from the Department of Tourism and Cultural Heritage of East Azerbaijan Province. Determining the value of geosites using the GAM method shows that the geosites of the fossil zone, Hampoil Cave and Gosheish Mineral Spring, Istibulagh, Garkh Kahol Cave and Chapar Cave, being located in the Z33 zone, have the necessary power for geotourism activities, but only Having natural potential alone does not lead to the expansion of geotourism activities.