Abstract: By the combination method of theoretical analysis and laboratory research, the regional division of goaf gas explosion in coal mine is studied. The research is divided into two parts: one is using carrying effect of goaf gas as the theoretical basis, and the flue gases are used as the tracer gas in the goaf gas flow test bench to carry out the similar simulation test. The range of strong flow area is divided according to the distribution of tracer gas in goaf.Second,based on the seepage and diffusion theory, using self-designed test device of gas migration, the scope of the seepage zone is determined according to the migration velocity of CH₄. At the same time, combined with the actual situation, the overlying strata caving and surface collapse caused by mining lead to disturbance and extrusion of the goaf gas flow field, which may cause gas explosion. So, combining the theory of gas spontaneous combustion with the "U" type combustion theory, goaf gas explosive areas mainly exists in the vadose zone and two lane caving zone.