In order to reduce the problems of high stress concentration and rock bursts in the hard roof rock of the extra-thick coal seam, the extra-thick hard roof hydraulic fracturing construction technology is adopted, and the hydraulic fracturing technology is used for fracturing at the 401101 working face of Mengcun coal mine in Binchang mining area. Field test, through the theoretical analysis of the fracture hole stress field and comprehensive analysis of various on-site monitoring methods. The results show that the borehole wall is damaged to different degrees at the fracturing position, resulting in three types of cracks: oblique cut, longitudinal and transverse fractures. After fracturing, the rock formations between the holes can penetrate well in the direction of the minimum horizontal stress. The vertical fracturing effect of the old roof is considerable; after the working face enters the hydraulic pre-cracking area, the frequency of high-level energy microseismic events is significantly reduced; after the working face advances to the high-pressure water pre-cracking area, the roof collapses sufficiently in the end range, and the support The peak working resistance and load increase coefficient are generally larger than those in the non-fracturing zone, and the empty load and leakage rate of the bracket are reduced. It shows that roof hydraulic fracturing technology can effectively provide strong technical support for the control of hard roof pressure relief in extra-thick coal seams.