Abstract: Based on the pressure releasing and permeability improved technology with seam slot cutting by high pressurized water jet, the ANSYS software was ap plied to the establishment of the model to simulate the variation of the seam displacement and stress under the different slot cutting width after the slot cutting by the hi gh pressurized water jet.According to the simulation results, the variation law of the disturbance influence from the seam slot cutting.Meanwhile, the site trial and applic ation of the technology was conducted in No.13 Mine of Pingdingshan Coal Mining Group and a investigation on a single borehole gas drainage and gas flow was condu cted with the slot cuting borehole and conventional borehole.The ANSYS simulation research showed that the slot cutting width difference would cause obvious variatio n of the displacement and stress around the seam.The increased slot cutting width would increase the disturbance influence scope of the seam, increase the cracking e xpansion of the seam and improve pressure releasing effect of the slot cutting seam.With the site test and application of the method, after the slot cutting in the seam C onducted with the high pressurized water jet, the gas drainage value with the slot cutting borehole would be 2.5 times higher than the conventional borehole.During the investigation period, the gas drainage and flow value with the slot cutting borehole was much higher than the conventional borehole and the gas drainage efficiency was highly improved.