GaN High Electron Mobility Transistor(HEMT) devices have superior advantages in high-frequency, high-power, high-temperature and high-pressure applications, and due to the excellent radiation resistance characteristics of gallium nitride materials, the devices are useful in radiation environments such as satellites, space exploration, and nuclear reactors. Although the theory and some existing experimental results have shown that GaN materials have excellent radiation resistance properties, in actual situations, the radiation resistance properties of GaN HEMT devices are greatly affected and challenged due to the influence of the device manufacturing process and structure. The major radiation effects of GaN HEMT devices are discussed, and the radiation research of GaN HEMT devices is reviewed.