Abstract: With the mature application of green mining technology in coal mines,the ecological environment of China's mining areas in China has been significantly improved,especially the ecological environment of ecologically fragile mining areas in the west has achieved positive succession. Therefore,in order to quantitatively evaluate the ecological environment of mining area and reflect the purpose of green mining technology to promote the improvement of ecological environment in mining area,this paper puts forward a set of evaluation index system of ecological environment in mining area based on water conservation mining technology in green mining. In this evaluation system,each index was weighted by using the more objective entropy weight method to reduce the subjectivity of experts when the index was weighted. The cloud model theory which can describe the randomness and fuzziness of the information was used as the modeling basis,and a set of water conservation mining ecological environment evaluation model based on entropy weight method and cloud model was constructed,which can quantify the impact of water conservation mining technology on mining ecology and the improvement effect of environment can realize the purpose of ecological environment evaluation of mining area based on water conservation mining technology. In addition,through field investigation,Halagou Coal Mine in Shendong Mining Area was selected as an example to evaluate the ecological environment of Halagou Coal Mine with the help of this evaluation model,and the rationality of the evaluation model was verified. The results show that：the ecological environment level of Halagou Mining Area is between the evaluation level of “excellent” and the evaluation level of “good”,which is generally in a good level. This evaluation result is consistent with the field ecological environment situation of Halagou,which verifies the rationality of the evaluation model. However,it can be seen from the evaluation cloud map that the evaluation results tend to be “good”,which also reflects that the ecological environment of the Haragou Coal Mine still has room for improvement. In general,through the construction and case verification of the evaluation model of water conservation mining,this paper shows that the evaluation model can objectively evaluate the ecological environment level of the mining area after the implementation of the water conservation mining technology,and can give suggestions for improving the ecological environment of the mining area,so as to achieve the purpose of scientific utilization of water conservation mining technology and realize the benign cycle of ecological environment in mining area.