Abstract: In order to ensure the gas outburst elimination and the gas control management of the protected seam, the effect of the pressure-relief in protecting coal seams is grasped, main regional distribution of pressure-relief gas is predicted; we got the effect of pressure relief, gas migration and distribution law of protected layer after the protection layer mining by using UDEC numerical simulation software of discrete elements; pressure relief gas is extracted by the method of drilling along gob-side entry retaining on the basis of the simulation results to achieve no pillar mining and eliminate the danger of coal and gas outburst in the stress concentration area of outburst coal seam. The test results show that gas pressure was reduced by 1.36 MPa, gas content reduced by 9.51 MPa and good extraction results are obtained.