Abstract: Under the condition of the close distance coal seam group in Baijiao Coal Mine, the air leakage is complicated and the air leakage is serious to the working face. Taking the area of 2274 working face as an example, this paper carried out the research of SF₆ tracer gas leakage testing technology, finds out the air leakage channel and grasps the law of leakage, and provides technical support for analyzing the hidden danger range of the old empty area in 2274 working face and takes preventive measures, and guarantees the safe mining of the working face.