Abstract: In order to explore the application potential of earth-air heat exchanger technology in the severe cold regions of Northwest China,this paper takes a earth-air heat exchanger system in Lanzhou as the research object,conducts actual measurement of its typical working conditions and analyzes the heat transfer performance and energy-saving effects under different working conditions. The results show that the average temperature of 2.0 m shallow soil in Lanzhou is 17.7 ℃ from June to September in summer. The average temperature from December to march in winter is 4.5 ℃. June,July,December and January have strong heat exchange potential. In Lanzhou,condensed water is not easy to occur in the earth-air heat exchanger system in summer. The outlet fresh air temperature is within the indoor comfortable temperature range,so there is no need for secondary cooling. The change of outlet air temperature and humidity curve of earth-air heat exchanger in winter is more gentle. In December and January,using the earth-air heat exchanger for preheating,the heat pump COP can be increased by 28.1%-30.3%,and the energy consumption can be reduced by 22.0%-23.3%. The simulation results show that the heat transfer efficiency of earth-air heat exchanger system is less affected by regional and seasonal variation.