Abstract: After the completion of the backfilling of the 10207 working face in Sucun Coal Mine, it is in the period of dynamic pressure influence. Air leakage in the goaf may cause spontaneous combustion of residual coal, posing a threat to the safety of the adjacent 10208 working face. The working face is adjacent to the 10206 goaf and 10208 mining face, with relocated villages and cracks on the surface. The study used SF₆ tracer gas instantaneous release method to release gas from negative pressure sealed walls and surface cracks underground, and collected and detected at points such as 10208 return air corner and related sealed walls. The results showed that the SF₆ concentration was high in the sealed areas of the 10207 and 10208 contact tunnels underground, and there was no air leakage on the surface. The main air leakage routes are: the outer section of the 10 coal north wing track roadway passes through the middle and inner sections, enters the 10207 return air duct, or directly enters the 10 coal north wing return air duct, enters the 10208 return air duct through the stop mining line, or enters the upper corner of the 10208 return air duct through the transportation duct and merges into the return air duct. The study has clarified the law of air leakage in the goaf of the 10208 working face, providing a scientific basis for targeted measures such as filling and plugging, controlling air leakage to ensure safe production in mines.