Abstract: Affected by the loose circle of surrounding rock of rock roadway, the sealing section of floor through layer extraction borehole sealed by "two plugging and one injection" technology is easily damaged, resulting in cracks, poor sealing effect and poor gas extraction effect. In order to improve the effect of gas drainage, this paper puts forward the solid-liquid two-phase compound sealing technology. Through the combination of solid sealing section and liquid sealing section, the dynamic cracks formed around the borehole in the loose circle and the cracks caused by the contraction of solid sealing section are timely sealed, the gas leakage channel is isolated, and the sealing performance of the sealing section is improved. The test is carried out in Shoushan No.1 Coal Mine of Pingbao Coal Industry. The results show that after 120 days of extraction, the gas concentration in the orifice of the test borehole is from 30% to 50%, which is significantly higher than that of the contrast borehole which is less than 20%. The technology effectively reduces the influence of surrounding rock loose circle on the sealing section of drainage borehole, and achieves the goal of improving gas drainage concentration and effect.