Abstract: In order to clarify the reasonable layout of the high-pressure hydraulic "cut-pressure" borehole spacing in steep and extra-thick coal seams, numerical simulation combined with on-site measurement was used to determine the coal wetting range of single-hole, double-hole and six-hole high-pressure hydraulic "cut-pressure" borehole, the wetting range of the coal mass was analyzed. The results show that when the water injection pressure is 40 MPa and the water injection time is about 16 days, the water injection wetting radius of the six-hole high pressure hydraulic "cut-pressure" borehole reaches 15.3 m in the saturated state, which can wet the coal in a large range; compared with the common high-pressure water injection technology, when the hydraulic slitting technology is used to assist the wetting of the coal mass, the water injection wetting range of the coal mass around the borehole is larger and the water injection effect is more significant; when the technology of high pressure hydraulic "cut-pressure" is implemented in 45^# coal seam at +500 m level in north Wudong Coal Mine, it is more reasonable to choose the spacing of "cut-pressure" borehole at 30 m.