Abstract: Gas drainage is a fundamental method of solving gas disasters of coal mine.Based on stress distribution features of borehole，the sealing mechanism of pressurized sealing technology was analyzed.Combined with the “two sealing and one grouting” technology，the new pressurized sealing equipment was developed.The experimental result showed that the equipment couldmeet the demand of 0.5 MPa grouting pressure.With the theoretical analysis，the technical parameters of 40118 mining face in Dafosi coal mine were obtained，the best grouting pressure was 0.4 MPa，and the reasonable sealing length was 12 m.The field test showed that the pressurized sealing technology could improve the gas drainage content by 50%，and the technology could ensure safety mining.