A new type of ion-exchange fiber with amino groups, called RPFA-I, was prepared. The amino modification and stretching resistance of RPFA-I were characterized by FTIR spectrum, SEM test, and auto-tensile test, respectively, and the removal of arsenite and arsenate in solution by RPFA-I was investigated. The obtained experimental results show that RPFA-I fibers have fine mechanical properties, and the amino functional groups have grafted to the surface of the matrix material. The adsorption results show that RPFA-I has a high capacity and good adsorption kinetic property in removal of arsenate and arsenite at the trace level. The removal efficiency was 70% for arsenite and 93% arsenate, respectively, at the concentration of 5 mg/L. The isothermal adsorptions were correspondent to Langmiur/Frundlich adsorption equation, and the adsorption kinetics was fit to the Lagergren pseudosecond order rate equation. The adsorption of the used adsorbent could be efficiently regenerated by RIM NaOH in a simple way. (C) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 110: 3934-3940,2008