An attempt was made to introduce a strong base anion-exchange group by radiation-induced grafting of vinyl benzyltrimethylammonium chloride (VBTAC) onto polyethylene film. Both two-step grafting and comonomer grafting techniques were tried owing to the difficulty of direct graft polymerization of VBTAC onto polyethylene. 2-Hydroxyethyl methacrylate (HEMA) and ethyl methacrylate (EMA), having the same backbone structure except that the hydroxyl group of HEMA was grafted onto the polyethylene film and then VBTAC was grafted to examine the reactivity of VBTAC with each grafted polyethylene film. Cografting of the binary mixtures of VBTAC and HEMA, or EMA, onto polyethylene film was also carried out.