Abstract: In order to ensure the effective drainage of the relieved gas in the protected coal seam by ground drilling in Huainan mining area,and realize the transformation of the protected high gas outburst coal seam into low gas coal seam, based on the distribution of overburden deformation fractures in the key overlying strata and the shear fracture mechanism of overburden movement in different rock (coal) seams, the ground drilling design parameters and structural processes of the overburdened protective layer in the Huainan mining area were proposed. The design parameters and structure technology of surface drilling for relieving pressure gas in protective layer were arranged in "O-shaped zone" or in the middle of separation zone where the fractureswere developed. The drilling structure was designed to usesoft rock and far rock layers to resist cementing, reaming near hard rock layers to avoid yielding well protection and reduce drilling shear fracture. The results show that the average gas extraction volume of a single well is 2.72 million m3, the drilling diameter is increased by 38%, the extraction volume is increased by 69%, the gas content of protected layer 13-1 is reduced from 9.02 m3/t to 3.61 m3/t, and the gas pressure is reduced from 3.8 MPa to 0.2 MPa. Good safety and economic benefits have been achieved.