Abstract The environment temperature has great effects on temperature field of cold storage refrigerator car and melting process of cold storage materials. NaCl aqueous solution was used as the cold storage material, Solidworks was used to establish physical model of the cold storage refrigerator car, Gambit for meshing and Ansys was used to make simulation calculation. The simulation results indicate that: with the rise of temperature, the melting process of storage plate will be fast, the time of latent heat discharge will be shorter. The temperature field of car can stabilize in a high temperature and the time is short. When environment temperature is 303K, cold storage material needs 70.2h to be melted into salt solution. The temperature field of car can stabilize in 293K for 73.6h. At this moment, environment and the temperature of cold plate existed large difference in, heat exchange is large and the heat flux is 2.75W/h.