Abstract: In order to analyze influence of surface air leakage of shallow-buried coal seam on mine ventilation system and goaf flow field, a coupling model of shallow-buried goaf flow field and roadway ventilation network under surface air leakage was established. According to feature of many branches in goaf network, a LDLT decomposition method was put forward to improve ventilation network calculation performance of Newton method. Taking surface air leakage of 15207 goaf of Hongliulin Coal Mine as an example, affection of large-scale surface air leakage on ventilation system and goaf flow field under different surface air leakage were simulated, and conclusions were gotten such as unnormal distribution of spontaneous combustion "three zones" in goaf caused by surface air leakage and surface air leakage should not exceed 5 m3/s, which provided technical support for safety mining of working face.