As an innovative manufacture technology,there has been a considerable development about the electron beam (EB) curing advanced composites in recent years.Epoxy resin,which has a lot of excellent properties and different molecular structure,is widely used as polymer matrix in composites.Most variety of epoxy resin has been confirmed to possess radiation reactivity and have already become a chief resin matrix used in EB curable composites.The radiation curing feature of bisphenol A epoxy resin was studied in this paper.Firstly,the technique of chemical extraction was used to test the curing degree of epoxy resin and the relationship between radiation dosage and curing degree was analyzed.The experimental data indicate the resin curing degree is increased with the rising of radiation dosage.But after the radiation dosage reached 100?kGy,the increasing extent became very small.The penetration process of electron beam in radiated resin and the structure of cured resin were studied.By analyzing radiation curing area of epoxy resin,it can be seen that EB exhibits intensively scattering in resin system.Around the radiation direction,the curing reaction can be initiated,and the penetration depth of EB will get to a fixed value on account of the gradual attenuation of electron energy.The results of observing the cured areas indicate that EB curing reaction spreads outwards layer upon layer around an active center when EB radiates the epoxy resin.The whole cured area is consisting of many lamellar structures.