Abstract: For aerospace electronic components to be worked in the vacuum environment, the device heating and the related heat dissipation must be specially considered. In this paper, the relationship between the temperature of a certain type of antifuse FPGAs working in the vacuum environment and the power consumption are studied, together with measures of heat dissipation. Through thermal vacuum test, the thermal value and the heat dissipation data of the devices with regard to different heat dissipation measures and various PCB conditions are obtained. Finally, the heat dissipation measures for the devices in vacuum environment are suggested. The device adopts a ceramic four-side flat 208-pin package (CQFP208) with heat sink. It is the first time in China to introduce comparable-sized heat sink (23 mm×23 mm) into such large size package (porcelain 29.2 mm×29.2 mm) and apply it to spacecraft. The test results and the heat dissipation measures proposed in this paper can serve as a reference for the applications of the electronic components with the same or similar kind of package.