Abstract: Risk grade evaluation of goaf is an important content of disaster monitoring, prevention and control.Based on the grey target theory, the grey entropy correlation analysis method is adopted, and the balance function is introduced to determine the comprehensive weight of the index.Eight evaluation indexes are selected to build the evaluation index system of goaf risk level.According to the comprehensive grey target model of variable weight, the target distance is calculated to form a quantitative target distance map of goaf risk level, and then the risk level is determined by the distribution of target distance on the target distance map of the test sample.Five test samples are used to verify the model, and the evaluation results are consistent with the actual risk level.At the same time, the gray entropy correlation analysis method is compared with the gray target model weight calculation method, which proves the rationality and accuracy of the gray target model.The results show that it is reasonable and feasible to use the comprehensive grey target model with variable weight to evaluate the risk level of goaf quantitatively, which can be used as the guidance and management decision-making basis of goaf disaster management engineering.