Abstract: The small coal mines goafs are prone to spontaneous combustion after shutting down and stop mining, which not only seriously affects the local environment, but also causes great impact on underlying coal seams after the formation of a large area of fire district. In order to find the key point of lower coal mining under the spontaneous combustion coals and take prevention countermeasures, this article analyzes the positional relationship between the 31201 working face and the small coal mines in addition the status of small coal mines' spontaneous combustion, mainly researches the influence of spontaneous combustion coal mines on 31201 working face from three aspects that the impact of fire, effects of poisonous gases and gas explosion.