With the increase in coal mining depth, the heat-harm problem has become increasingly serious. This paper introduces the design process of deep HEMS cooling system in Tangdong coal mine heat-harm treatment, and expounds the working principle of deep HEMS cooling system. On the basis of computing the cold load in cooling face, it selects the main equipment type, decides the cooling system process, analyzes system engineering economy, and compares with other cooling methods. It provides useful references for similar mine heat-harm treatment.