Abstract: In order to provide a theoretical basis for the location selection of emergency rescue station of the long railway tunnel at high altitudeand to improve the design requirements for disaster prevention and evacuation of highaltitude railway tunnels, taking the typical extra-long double-track tunnel at high altitude as the background, a fullscale fire model and evacuation model are established by using FDS and Pathfinder. By analyzing the vertical visibility,distribution laws of temperature and required safety evacuation time(RSET) of different locations of emergency rescue stations at different altitudes, the available safety evacuation time(ASET) and required safety evacuation time（RSET） in each case are obtained, thus the locations of emergency rescue station at different altitudes are determined. The results show that: under the altitude of 3 000-4 000 m, the ASET and RSET both meet the requirements of 6 min; the location selection of high-altitude railway tunnel should be based on the principle of minimum RSET;under the altitudes of 3 000 m, 3 500 m and 4 000 m, the optimal locations of the emergency rescue stations are 10km, 20 km and 15 km away from the portal respectively.