Abstract: In order to improve the permeability of coal seam and the sealing quality of gas drainage borehole, strengthening the effect of gas drainage and eliminating the danger of coal seam outburst, this paper proposed the drilling-slotting-sealing technology based on the mechanism of high pressure water jet breaking coal. That is to cut radial annular seam groove around gas extraction borehole and sealing hole section, and then grouting sealing hole. The effect of gas drainage borehole applied the drilling-slotting-sealing technology is verified through field test. The field test shows that: the gas concentration of the borehole using drilling-slotting-sealing technology increases 20% and 30%, and the net amount of gas extraction is about 1 times higher than that of conventional drilling, which realizes pressure relief and permeability improvement of coal seam and improves the tightness of drilling.