Abstract: Nan’an City, located in the southeastern hilly region of Fujian Province, is highly prone to geological hazards due to its unique geographical setting, complex geological structure, and frequent human activities. These hazards pose serious threats to local lives and property. Therefore, it is necessary to explore the factors that contribute to the occurrence of geological disasters in Nan’an City. Based on remote sensing images and geological data, this study employs the geographic detector model to systematically analyze the influencing factors of geological hazards in Nan’an City. The main findings are as follows: (1) A total of 209 geological disaster sites were identified in Nan’an City, including three types: landslides, debris flows, and landslides. (2) Eight key factors related to the spatial differentiation of geological disasters were determined, and the explanatory power of each factor, as well as the results of their pairwise interactions, was obtained. (3) The frequent occurrence of geological disasters in Nan’an City is mainly attributed to the combined effects of tectonic activity, topographic uplift, rainfall erosion, and human activities. This study provides theoretical and data support for the risk assessment and prevention of geological disasters in Nan’an City.