The coordinated co-mining of coal and gas is the main development direction of green mining in coal mine. At present, a comprehensive and scientific evaluation index system of coal and gas co-mining has not been constructed; in addition, due to the unknown and uncertainty of the index, it is difficult to determine the reasonable index weight, and there is a lack of accurate coal and gas co-mining evaluation model and method. In view of this, the evaluation system of co-mining of coal and gas is constructed based on four factors: geological occurrence conditions, economic cost conditions, technical level conditions and safety management conditions. Coal seam and gas occurrence conditions, coal seam permeability, coal seam stability and other 24 factors as index layer. In this paper, a combination weighting method based on game theory is proposed, which effectively combines the objective weight obtained by entropy weight with the subjective weight obtained by Analytic hierarchy process to obtain reasonable index weight. the influence of index on coal and gas co-mining is as follows: coal seam and gas occurrence condition > coal seam gas permeability > pressure relief and permeability increasing condition > co-mining equipment > coal seam stability > geological structure complexity. Combining the combination weight with the approximate ideal solution ranking method, the evaluation model of CW-TOPSIS co-mining of coal and gas is constructed. The feasibility of co-mining of coal and gas in a coal mine is evaluated by using CW-TOPSIS model, and the result is "good" grade. The model is analyzed and discussed with Bayesian model, fuzzy comprehensive evaluation method, evaluation model based on cloud model and Dmurs theory. The research shows that CW-TOPSIS model can not only accurately reflect the evaluation grade, but also reflect the preference degree of evaluation results, with higher accuracy, and the model has higher application value.