Rotational molding, which is widely used in furnishing, entertainment facilities, automotive and boats, military industry and other fields, is a forming method used to produce hollow thermoplastic products. Temperature is the most important process parameter in the rotational molding process, so accurate temperature modulation and control are undoubtedly the main way to ensure product quality. During the rotational molding process, temperature in the oven is very high. Current temperature measuring device cannot make real-time measurement and cannot provide the necessary reference for accurate temperature modulation and control. This article provides an analysis of a wireless temperature measurement device which is used in high temperature enclosed environment, researches the structure, the barrier principle of the temperature measurement device. Finally, tests have been done to verify the working performance. Accurate monitoring and control of the temperature parameter during the rotational molding process can not only improve the working efficiency and energy efficiency of the rotational molding machine, but also provide the reference to design the rotational molding device and molds.