Abstract: According to the complicated borehole sealing technique and high operation requirements existed in the available borehole sealing of the gas drainage, t he limited application scope, low gas drainage concentration, short effective gas drainage period of the borehole and other technical difficulties, a new borehole sealing device was applied to seal the borehole. The paper stated the borehole sealing principle of the new borehole sealing device. A comparison analysis was conducted on t he gas drainage concentrations between the new borehole sealing device + cement grout borehole sealing and the polyurethane + cement grout borehole sealing, the e xperiment results showed that with the application of the new borehole sealing device + cement grout borehole sealing, a single borehole sealing would only require 25 min and the polyurethane + cement grout borehole sealing would require 55 min for a single borehole. After 48 days of the borehole sealing and gas drainage, the aver age gas volume fraction of the new borehole sealing device + cement grout borehole sealing was about 33% and was higher than the gas volume fraction 4% drained fr om the polyurethane + cement grout sealing borehole. The borehole sealing technique of the new borehole sealing device was simple and after the borehole sealing, th e gas drainage concentration from the borehole would be high and the gas drainage time would be longer with a promotion and application value.