Abstract: Air leakage in goaf easily leads to coal spontaneous combustion, gas accumulation and other disasters, threatening the safety of coal mine production. In order to study and master the distribution of air leakage flow field in goaf, taking 3308 working face of Liangbaoshi Coal Mine as the research object, a three-dimensional model of goaf was established, and the distribution function of resistance coefficient and porosity was constructed. The air leakage flow field in goaf was simulated by CFD software. The results show that air leakage exists objectively in the face of goaf, and the distribution of air leakage flow field has obvious regional characteristics in all directions; the main air leakage in the goaf occurs in the range of 0-10 m inclination of the working face, and the sealing work in this range should be strengthened to isolate the air leakage passage; the distribution trend of air leakage along the inclination of the working face obtained by numerical simulation is basically the result of field measurement. The agreement verifies the correctness of the numerical simulation. The above analysis provides a theoretical basis for reducing air leakage in goaf and preventing spontaneous combustion of residual coal in goaf.