Abstract: In this paper,the epoxy acrylate prepolymer was synthesized by the reaction of epoxy resin E-44 and an acrylic acid.The prepolymer was used to form the hard permanent layer in the fabrication of the build-up multilayer printed circuit board.In the synthesis reaction,the influence factors such as reaction temperature,catalyst,inhibitor and dose were investigated.The result showed that the optimized reaction parameters were temperature 90℃,N,N-methyl toluidine catalyzer 1% and hydrochinone inhibitor 0.5%.