O - methyl acryloyl - oxygen ethyl dimethyl epoxypropyl ammonium chloride (ODEAC), an active intermediate, was synthesized with 2-dimethylamino ethyl methacrylate (DM) and epichlorohydrin (ECH) as the main raw material. The influence of the solvents, reaction temperature, material ratio and reaction time on product conversion and the epoxy value were respectively discussed using single factor experiment, to discusses the optimum synthetic process conditions: the reaction temperature 60 ℃, using isopropanol as the solvent, n (ECH) : n (DM) = 1:1.6, reaction time is 4 h, the target product conversion is 91.67%. And the structure of the product was characterized by FTIR and 1HNMR.