Abstract: Coalfield fires resulted from coal spontaneous combustion has already become one of the major casualties of coal production. Large-scale spontaneous combustion of coal seam in north China not only burns wasted coal resources and endangers safe production of coal mining, but also brought a series of environmental disasters,which becomes a serious challenge for sustainable development and westward-shift strategy of China's coal industry. This paper analyses the environmental effect of coal fires from geology, atmosphere, water, soil, ecology and influence of people's health. Finally, some suggestions of environmental restoration and treatment on coal fires were put forward.