For frozen soil tunnels, when the frost heaving pressure used in the lining is different, different fortification measures should be considered to achieve the purpose of safety and economy. Taking Kunlun Mountain Tunnel as the background, the classification standard of frost heaving force is put forward for the first time. The research results show that for single-track railway tunnels, the frost heaving force can be divided into three grades by two generalized frost heaving force values of 0.07MPa and 0.3MPa under deep burial conditions and two generalized frost heaving force peaks of 0.3MPa and 0.7MPa under shallow burial conditions.