Abstract: Aimed at the problems of gas anomalies in the goaf of Shigetai Coal Mine, based on the theory of spontaneous combustion of the residual coal in the goaf, we analyze and summarize of the laws of the residual coal in the goaf of shallow buried depth and close distance seams, the laws of the air leakage in the up and down well, the law of gas migration in the goaf and so on. At the same time, taking the nitrogen oxide contained in the flue gas as the “marker gas”, we determine the cause of the gas anomalies in the goaf, which is that the small coal mine stripping destroys the airtight of the big coal and the flue gas migration and accumulation in No.2 panel. The ground drilling grouting sealing technology is used to fill the air leakage tunnel and the gas returns to normal level in goaf.