The polyethylene (PE) mumbrance for adsorbing uranyl ion was prepared by radiation-induced grafting of acrylonitrile (AN) onto PE hollow fiber, and its subsequent amidoximation on cyano groups of poly(AN) graft chains. The adsorption characteristics for the chelating hollow fiber membrane was examined after the solution of UO₂²^+ permeated across the chelating hollow fiber membrane. The inner and outer diameter increased with increasing grafting yield, whereas the pure water flux and pore diameter decreased with increasing grafting yield. The adsorption of UO₂²^+ by the chelating hollow fiber membranes increased with increasing amidoxime group. The adsorbed amount of UO₂²^+ by the chelating membrane was higher in uranylacetate solution than uranylnitrite solution. Amidoxime group-chelating fiber membrane showed a high selectivity for UO₂²^+ in the presence of Na¹^+) and Ca²^+ even through there is a high concentration of Na＾1^+ and Ca²^+ in the inlet solution.