Abstract: In order to study the changing law of slope stability at the shallow buried area in Heishan Surface Mine, and to ensure the safety of the mining process, we carried out the stability study for open-pit mine, and calculated slope safety factors for different depth by Geo-Studio analysis software, and respectively implemented stability analysis under non-spontaneous combustion condition and key layer control condition. The results show that the reduction extent on the stability coefficient of the end slope is up to 36% with the existence of the burned coal seam; and the stability coefficient of the slope in the fire zone decreases linearly with the increase of the mining depth. When the height of end slope reaches to 170 m, the stability of the slope is reduced to the limit equilibrium state. The most dangerous slip surface is tend to slide out from the burning coal seam, the slop stability could be improved by increasing the mechanical parameters of coal seam that is as the key layer.