Abstract: Some rock burst mines are affected by disasters such as water, fire and gas. The wide coal pillar is set up in the mine, which increases the risk of rock burst. The roof lateral pre-cracking can effectively reduce the stress concentration inside the coal pillar and protect the safety along the goaf. In this paper, the 35 m wide coal pillar in Cuimu Coal Mine is taken as the research object. The influence of lateral roof overhanging on the stress distribution of coal pillar is analyzed. The effect of different roof pre-splitting parameters is analyzed by numerical simulation and in-situ micro-seismic monitoring. The study shows that the peak area of the lateral stress in the goaf is the area with the maximum stress on the roof. The roof pre-splitting can be used to achieve better pre-splitting effect. The pre-cracking method was applied in 22305 and 22307 working faces of Cuimu Coal Mine, and the impact risk was significantly reduced.