Abstract: The stress disturbance of fully mechanized caving face is violent and the stress concentration of advanced abutment pressure is higher, which is easy to cause the coal-rock dynamic disasters such as rock burst. Based on the geological conditions of 2341 fully-mechanized working face in coal mine production, the paper uses FLAC^3D to simulate the bearing stress distribution characteristics in front of the working face, and introduces the large diameter borehole pressure relief mechanism and technology practice. The results show that the peak stress ahead of working face is 55.5 MPa, and the stress concentration ratio is about 2.5; large diameter drilling can effectively increase the fracture density of coal and reduce the stress concentration and stress gradient; after the unloading of large diameter borehole in the working face, the measured maximum drilling cuttings is 2.7 kg/m to 3.6 kg/m, below the critical value of 4.8 kg/m, and the safe mining of working face is realized.