Heat exchange occurs during the transportation of carbon dioxide through pipelines. When the temperature of a substance increases (decreases) by 1 ℃ per unit mass, the heat absorbed (released) is called the specific heat capacity of the substance. The heat exchange capacity is closely related to the specific heat capacity of the transmission medium. Therefore, the study of the change of carbon dioxide specific heat capacity is of great practical significance to the study of carbon dioxide pipeline transport law. Hysys is used to simulate the change of specific heat capacity of pure carbon dioxide with temperature and pressure,