|| Poly(vinyl benzylchloride-co-styrene-co-hydroxy ethylacrylate) copolymer were synthesized by free radical polymerization. The copolymer was aminated with various aminating agents, including trimethylamine, triethylamine, tripropylamine and tributylamine. The structures of the aminated copolymer solutions were confirmed by Fourier transform infrared (FT-IR) analysis. The membrane properties, such as water content, ion exchange capacity, electrical resistance, ion conductivity and permselectivity for nitrate, were also measured. The maximum water content, ion exchange capacity, electrical resistance and ion conductivity were 45.5%, 0.90 meq/g dry membrane, 60.2 Ω cm2 and 0.0109 S/cm, respectively.