Abstract: During the tunnel construction process, the high temperature at the heading face seriously affects the health of construction workers and the construction progress. Taking a tunnel project the background, firstly, the heat source of the tunnel is analyzed, and it is found that the main heat sources include mechanical heat release, human body heat dissipation and blasting heat then, a variety of working conditions are established for numerical simulation, which shows that the high temperature area in the tunnel is mainly concentrated within 20 m of the arch top, the distribution is uneven, and it is impossible to meet the normal environmental requirements only by ventilation and cooling, and the temperature at the heading face can reach a relatively comfortable temperature by spray flake ice; finally, in order to verify the effectiveness of the measures, a flake ice spraying system is added in the tunnel, and the temperature at the arch top the arch springing before and after the cooling measures are taken is compared. The results show that the use of flake ice spraying combined with normal air supply can effectively reduce temperature in the tunnel by 4～5 ℃, and provide a relatively comfortable environment for workers. The research verifies the guiding role of numerical simulation technology and provides reference and reference similar high-temperature tunnel construction.