Abstract: In view of current high cost,weak sealing effect,complicated operation,poor reliability and other problems in domestic gas drainage borehole sealing,a new sealing technology of airbag delayed expansion with pressure grouting for gas drainage borehole is put forward.The mechanism is discussed;corresponding delayed expansion airbag and sealing grouting materials are developed.The borehole sealing depth,length,radius and related parameters such as grouting pressure are analyzed in theory angle.Application tests in Rujigou Mine of Shenhua Ningxia Coal Industry Group show that the airbag delayed expansion with pressure grouting sealing technology has the advantages of simple operation and high reliability.As a result,gas drainage concentration can be increased by 28% on average.