Copolymers of glycidyl acrylate with each acrylonitrile and styrene was prepared using benzoyl peroxide as free radical catalyst in bulk. Monomer reactivity ratios for glycidyl acrylate-acrylonitrile copolymerization, and for glycidylacrylate-styrene copoymerization were respectively determined. For the purpose of investigating the reactivity of epoxy group in side chain of copolymers, these copolymers were reacted with some amines and it was found that epoxy group in copolymers was considerably reacted with amines, from results of nitrogen analysis.