Abstract: Since the popularization and application of small coal pillar roadway protection technology in Yanzishan Mine, the coal pillar of roadway adjacent to small coal pillar is affected by coal mining disturbance, which has caused problems such as large roadway deformation and difficult support, which seriously affects safety production. In view of this, Yanzishan Coal Mine adopts hydraulic roof cutting and pressure relief technology, which uses high-pressure hydraulic cutting to form directional cracks and uses expansive agent to realize hole cutting and penetration; The principle of this technology is to form directional cracks with a depth of about 300 mm by high-pressure hydraulic cutting, and then use expansion agent to expand the cracks to about 600 mm, so as to realize the radial penetration of presplitting drilling holes with a spacing of 1.0 m, and effectively realize the cutting of large-area suspended roof. The application effect in 8210 air entry shows that this technology can effectively cut off the side roof of coal pillar in 8210 roadway, weaken the integrity of the roof in 8210 working face, reduce or even eliminate the adverse impact of the lateral support pressure of adjacent goaf on the roadway along goaf with small coal pillar, and the pre-cracked hard roof will collapse in goaf in time, thus completely solving the problems of large deformation and difficult support of the roadway near goaf with small coal pillar.