As urbanization accelerates, the subway, with its unique advantages of high speed and high capacity, plays an increasingly important role in the process of urban development. However, with the accelerating pace of subway construction in the country, subway accidents have occurred frequently in the recent years, exposing the vulnerability of subway operations. This paper analyzes relevant research at home and abroad to establish the concept of subway station operation vulnerability based on the attributes of exposure, susceptibility, and adaptability. Based on this concept and operational accident statistical analysis, an evaluation index system is established. Combining the theories of rough sets and extension sets, a multi-level extension evaluation model is constructed. Finally, the multi-level extension evaluation model is applied to conduct case evaluations and provide recommendations.