In order to create favorable conditions for the safety production of the working face, this study adopted theoretical analysis, on-site measurement, data analysis and other methods to study the weakening and disaster reduction mechanism of directional hydraulic fracturing in deep thick and hard rock layers. The research results indicate that: ① Based on theoretical analysis, it has been found that different fracture forms of thick and hard rock formations in fractured layers can reduce the fracture step distance of thick and hard rock formations, effectively destroying the conditions for the occurrence of high-energy events. ② Through on-site drilling and observation, it was observed that the target rock layer developed various types of fractures after hydraulic fracturing, and the integrity and continuity of the target rock layer were damaged. ③ Comparing and analyzing the frequency and energy distribution of microseismic events in the unfractured and fractured areas, it was found that the number of high-energy microseismic events (>10000J) in the fractured area was 1, which was a 97.7% decrease compared to the number of high-energy microseismic events (44) in the unfractured area. The peak energy in the fracturing zone decreased by two orders of magnitude compared to before fracturing. The research results fully demonstrate that directional hydraulic fracturing plays an extremely significant role in the weakening and disaster reduction of thick and hard rock layers.