Abstract: The environmental comfort in the train depends not only on the operating effect of the air conditioning unit,but also on the thermal insulation performance of the vehicle body enclosure structure. Taking a certain intercity train as study object,the heat transfer coefficient of certain typical cross sections of the vehicle body enclosure structure is numerically calculated by CFD,and the heat transfer coefficient of the cross section is tested through experiments. Through simulation calculation and field test analysis,it is found that the heat insulation performance of the vehicle body enclosure structure meets the requirements of heat insulation. By comparing and analyzing the results of simulation and field tests,it is found that the error between the simulation and field results is within 10%, which shows that the simulation calculation results of the heat transfer performance of the enclosure structure are reliable and have reference significance.