Abstract: This study investigated the impact of total radiation dose on the mechanical and electrical properties of epoxy resin adhesive and epoxy resin potting adhesive with modified nano silica fillers, materials commonly used in spacecraft. The property changes of these adhesives under various doses of γ-ray (⁶⁰Co) radiation were compared. The findings reveal that both types of epoxy resin adhesives exhibit good tolerance to radiation up to 10⁷ rad(Si). Notably, the performance inflection points for both adhesives occur at approximately 10⁴ rad(Si) of total radiation dose. The mechanical and electrical properties of the potting adhesive with modified nano silica fillers remain largely stable after radiation exposure. In contrast, the breakdown voltage of the adhesive without fillers decreases by about 15% following radiation. Additionally, the dielectric properties of both adhesives show slight improvement post-radiation. This research provides valuable insights for satellite structural bonding design, radiation protection strategies, and lifetime prediction of epoxy resin adhesives in space applications.