Abstract: To satisfy the requirements of missile electronics operating under high-temperature conditions, the paper designs a thermal energy storage device that effectively controls the temperature of the equipment. According to the performance and related technology requirements of the equipment, the structure of the thermal energy storage device is designed, and three thermal energy storage devices with similar structure frames are respectively made by H62 brass, 5A06 aluminum and foam copper based paraffin phase change material(PCM). Simulated heat source which has the same operational heat consumption as the actual equipment is designed for the test of the thermal energy storage device, and the test compares physical capabilities such as the thermal energy storage, the heat conductivity of the three devices. Results show that the PCM thermal energy storage device meets the temperature control requirements and has distinct advantages in thermal energy storage and weight, and it can be applied in similar platforms.