Abstract:Before and after ending of deep open-pit coal mine,geological disasters such as slope sliding and surface deformation probably occur. Taking Fushun Western Open-pit Coal Mine as an example,the geological background conditions of the disasters are the inclined slippage body of the western section of the northern slope,subsidence slippage body of the eastern section of northern slope,and the sandwich body of southern slope,while the key factors inducing disasters are the mining features of open-pit coal mining,final slope formed,the compound effects formed by underground mining and open-pit mining and no-water-drainage due to the ending of the mining,and the effects of the change of hydrological geology on slope rock mass. Calculation shows that the stability of the slope will decrease gradually and cause disaster to endanger the safety of the city and enterprises. Three suggestions including setting up the theory of open-pit coal mining,engineering technology preventive measure,and statute regulation and supervision management are put forward.