In order to improve the high-temperature working environment of geothermal in Woxi pithead kilometer deep mine，the paper analyze the main heat source and damage.It adjusted the ventilation structure and established a new ventilation which designed and constructed a special return air shaft，installed a main fan on the surface，transformed the original east air shaft（return air shaft） into intake air shaft，stopped the fan of the original ventilation system.The site implementation showed that the new ventilation system directly exhausted the pollution and high temperature air from the mine deep area，the outlet air temperature nearly increased 2 ℃，ventilation and heat removal capacity increased by 4.3 times，total ventilation ability increased by more than one time.The air sours of large quantity with high enthalpy in summer，the heat of intake air could not fully be absorbed by the upper low temperature rock，most of the high enthalpy air is carried into the deep area，and make the whole mine air temperature is rising，which suggested that the greater the intake air volume into the shaft does not mean that the mine ventilation cooling effect is better.It also showed that the effects of ventilation cooling for deep mine must be comprehensive evaluation of intake air volume and temperature and than puts forward that the main fan operation scheme will be optioned to seek economic air volume to reduce the air sours enthalpy in summer.