Abstract: Multi mining effect of roadway surrounding rock has become an urgent problem to be solved in coal mine safety mining under the condition of extra thick coal seam fully mechanized caving mining.According to the technical problem of mining influence in extremely thick coal seam by sub-level caving mining in Buliangou coal mine, using structural mechanics theory to set up the mechanics model of the overburden strata structure and analyze of the stability of surrounding rock under the influence of mining. Get the overlying rock the key block subsidence in the analytical formula of breaking. Three dimensional numerical model was established to study the displacement and plastic zone distribution of surrounding rock, and the deformation and failure law of surrounding rock under mining influence were obtained. Field measurements show: F6103 face rear 15~25m roadway is affected by the first mining effect, and the mining disturbance has little influence on the stability of surrounding rock. F6103 face rear 15~25m roadway is affected by the second mining effect, the rock pressure of the surrounding rock is more severe, and the deformation is obviously increased.