Epoxy resins are extensively utilized in the nuclear industry, high-energy accelerators, and deep-space exploration due to their strong corrosion resistance, good thermal stability, high mechanical strength, and exceptional electrical insulation properties. However, ionizing radiation present in these application environments can degrade the three-dimensional network structures of epoxy resins, significantly impacting their service performance. This presents a significant challenge for reliability assessment, making it necessary to elucidate their irradiation damage behavior. This paper reviews the recent research advancements on the radiation damage behavior of epoxy resins, emphasizing the effects of chain crosslinking and scission induced by various irradiation conditions on their chemical structures and physical properties, including mechanical properties, thermal stability, thermal conductivity, and electrical properties. Finally, future research directions deserving special attention are discussed, considering the current gaps in understanding the radiation damage in epoxy resins.