Abstract: NANO-SiO₂ particles were added in the bisphenol A epoxy resin. The curing characteristics of the NANO-SiO₂ / epoxy resin system were researched. The effect s of NANO-SiO₂ content on reaction temperature , gel fraction ,dimension of the cured area and dynamic mechanic performance of the elect ron beam ( EB) cured epoxy resin systemwere investigated. The result s show that the exothermal peak of the curing system decreases with the increasing ofNANO-SiO₂ content , and a small amount of NANO-SiO₂ particles cont ribute to increasing the dimension of the curedarea , gel f raction , glass temperature and high temperature modulus. The growth mechanism of the system withNANO-SiO₂ particles is similar to that without NANO-SiO₂ particles , although the propagation path of EB is changed byNANO-SiO₂ particles.