Abstract: Abstract：In order to control the main mining coal seam in Dingji Coal Mine 13-1 the occurrence of coal and gas outburst, use of protective layer mining and ground drilling drainage was protection of 13-1 coal seam gas pressure unloading governance gas technology. On the basis of the high gas pressure and high stress condition in No. 13-1 coal seam, the scope of protection of lower protective seam mining in Dingji coal mine by using theoretical analysis, numerical simulation, field testing. The research result shows that stress discharging angle in trend direction is 60°, and in inclined direction the angle are 78°and 82°.The field testing results are agree with the simulation results.