Abstract: During the mining of shallow-buried coal seams, full-thickness cutting of the overburden strata produces vertical fissures, The fracture cause air leakage in the working face and the mined-out area, threatening the safety of mineral production. In order to analyze the fracture development and air leakage characteristics of overburden strata in this kind of geological conditions, the simulation and evolution of the fractures in the mined-out area were carried out through physical similarity simulation experiments. Further numerical simulation verification was carried out, and it was proposed that blocking prevention measures could effectively reduce the air leakage in the working face, and the parameters, such as viscous resistance, distance and construction period of the blocking, were determined, and get good feasibility. Based on the research of 30100 face in Nanliang Coal Mine, this paper has made a good reduction of crack development in the mining process of 30100 face, and the practice has proved the rationality of the parameters of simulation prevention measures. This research has a very good theoretical guidance significance for the prevention and control of spontaneous combustion of leftover coal and water control in coal mine production, and it has good economic benefits for the safe production of coal mines.