Abstract: In order to find out the main causes of heat damage and the thermal comfort of workers in the 111307 fully mechanized working face in Kouzidong Coal Mine, the thermal environment parameters and surrounding rock temperature during the maintenance and production periods of the 111307 working face are measured on site.Based on the apparent temperature and PMV-PPD index, the distribution characteristics of thermal comfort of the working face are comprehensively studied, the chilling requirement of the 111307 working face is calculated, and a multi-level cooling optimization scheme is proposed.The results show that from the machine lane to the cut-hole to the wind lane, the apparent temperature and the predicted mean vote (PMV) of the working face during the maintenance period and the production period all shows a trend of first increasing and then decreasing.During the production period, the proportion of areas above the relatively high-thermal risk area increased by 43.4% compared with the maintenance period, and the area above the uncomfortable area increased by 54.8% compared with the maintenance period.The distribution positions of the high-thermal risk area and extremely uncomfortable area during the production period and the maintenance period are different.The chilling requirement of 111307 working face is 4 072.89 kW.The application of large air coolers to cool the machine tunnel area and the corner of the working face in a graded manner, and the arrangement of hanging small air coolers in the working face cut-hole to cool the dense area of personnel and equipment, can effectively improve the utilization efficiency of cooling capacity in theory.