[Objective] The ecological security situation of a underground coal mining area in Datong City, Shanxi Province was comprehensively evaluated in order to provide a scientific basis for the ecological protection of the underground coal mining area. [Methods] Based on various indicators from the mining area from 2017 to 2021, an ecological security evaluation index system was constructed based on the three aspects of the PSR model (pressure, state, and response). The combined weight coefficient was determined by the cooperative game method, and the extension cloud model was used to analyze the ecological security situation of the mining area. [Results] Under the pressure index, the evaluation grade of natural population growth rate (C₂) was level Ⅲ, indicating that the birth rate and death rate were not evenly distributed, and the evaluation grades of other indicators were all at level Ⅱ. Under the state index, the evaluation grade of vegetation coverage rate (C₈) was at level Ⅰ, indicating that the coal mine area had a high vegetation coverage rate. The evaluation grade of tailings pond drainage measures (C₉) was at level Ⅲ, having reached the unsafe level. The evaluation grades of other indicators were at level Ⅱ. Under the response indicators, the comprehensive utilization rate of waste (C₁₅) and the growth rate of scientific research investment (C₂₀) were at level Ⅱ. The growth rate of environmental protection investment (C₁₉) was at level Ⅲ, and the evaluation grades of other indicators were at level Ⅰ. [Conclusion] From 2017 to 2021, the response to ecological security of this underground coal mining area had significantly enhanced, but the ecological pressure and the current state were still severe. Targeted protection measures should be taken to maintain the local ecological security.