Grafting polymerization of aerylamide (AAM) onto polyether urethane (PEU) was investigated in aqueous solution by using eerie ammonium nitrate (CAN) aa initiator．The grafted polymers were synthesized as follows：(i) a variety of PEU from poly (oxytetramethylene) glycol (PTMG)，4，4'-diphenylmethane diisoeyanate (MDI)，and ethyleneamine (E) or butandiol (B) as extender under different reaction conditions were used to east into films；(ii) grafting of PAAM onto PEU film by using CAN and (iii) the grafted PEU substrate was then extracted with boiling distill-ed water．to remove the residues of AAM and PAAM homopolymer．The PEU films of varying thicknesses with either B or E as extender could be easily grafted by A A M．The grafting polymerization was verified from the fact that the grafted substrates be-come opaque and possessing higher percentage of water absorption than the original one，and from the scanning electron microscopy photographs with saHent mierograph showing grafts of maeroehain on the surface of fiIm．In addition，the faetors that in-fluenee the grafting eopolymerization were studied，and the mechanism of grafting polymerization has been proposed．