Anion-exchange membranes were prepared with 2,3-epithiopropyl methacrylate (ETMA)-dodecyl methacrylate (DOMA)-methacrylamide propyl trimethyl ammonium chloride (MAPTAC) terpolymers. Transport of ferric ions in sulfuric acid solution through the membranes was studied by using a system containing Fe-2(SO4)(3) in sulfuric acid solution (left-hand side) and sodium oxalate solution (right-hand side). Ferric ions in sulfuric acid solution could be fast transported through the anionic ETMA-DOMA-MAPTAC terpolymer membranes. The transport of ferric ions was greatly affected by the composition of the membranes and the concentration of sodium oxalate in a receiving solution. Ferric ions could be selectively transported from the mixed solutions containing ferric ions and other metal ions such as cadmium or aluminum ions. It was assumed that ferric ions were transported as anionic oxalate complexes against a contrary transport of oxalate ions through the ETMA-DOMA-MAPTAC membranes.