The complex geological conditions in Dashe mine and spontaneous combustion of coal seam restricted mine safety production, and there were 22 times spontaneous combustion of coal in its history. Due to top coal caving mining in No.2 coal seam, coal spontaneous combustion had been a major threat to mine safety production. In order to ensure safety of mine production and prevent spontaneous combustion in goaf, fire monitoring and early warning system was applied to realize temperature monitoring, gas composition determination and spontaneous combustion warning in deep goaf, which could detect spontaneous combustion in working face goaf immediately. At the same time, the depth and degree of spontaneous combustion could be determined as well, which provided more accurate information for fire prevention and control measures.