Abstract: Structural coal seam has the characteristics of low permeability, low strength and high gas content, and it is easy to appear the phenomenon of plugging and blasting, which directly leads to the difficulty of gas extraction in this kind of coal seam. In order to solve the problem of gas extraction caused by low permeability of structural coal seam, the existing anti-reflection technology of coal seam and its advantages and disadvantages are analyzed, a regional hydraulic cavitation pressure relief and anti-reflection technology is introduced, and the hydraulic cavitation pressure relief and anti-reflection gas extraction technology system is put forward, including hydraulic cavitation drilling and punching equipment, coal water separation and coal quantity measurement system, high and low negative pressure independent gas extraction system. Taking the test mining area as the engineering background, the existing anti-reflection technology of coal seam and its advantages and disadvantages are introduced and analyzed. The regional hydraulic cavitation pressure relief and reflection improvement technology is put forward, and a regional hydraulic cavitation pressure relief and reflection improvement technology system is formed, which is mainly composed of hydraulic cavitation drilling and punching equipment, coal-water separation and coal quantity measurement system, and high and low negative pressure independent gas extraction system. Field tests are conducted with equal spacing of 7 m, 8 m, 10 m, 12 m and variable spacing hydraulic cavitation schemes, and the pumping effect of different borehole diameters is analyzed, and the gas extraction effect of single hole and group hole is compared and analyzed. The results show that the hydraulic cavitation with variable spacing can effectively guarantee the effect of coal body pressure relief and permeability improvement, solves the unbalanced problem of tunneling and pumping, and provides a new technology to solve the problem of gas extraction caused by low permeability of structural coal seam.