Abstract: Thermal vacuum electromagnetic pump is a kind of electromagnetic pump used in the vacuum and high temperature environment, and the lack of heat transfer leads to high temperature of the equipment, which will make the performance of the structure and functional materials decreased dramatically. In this paper, numerical calculation was used to calculate component temperature distribution of small NaK thermal vacuum electromagnetic pump researched by the China Institute of Atomic Energy. The results show that the thermal control measures of vacuum insulation layer applied on pump channel wall and spray black coating on the shell are effective, which can reduce the temperature of the components in the equipment, especially the excitation coil, and improve the service life of the equipment.