Polyethylene (PE) and polypropylene (PP) films were grafted with an acrylic acid/2 hydroxyethyl methacrylate (AAc/HEMA) mixture under nitrogen atmosphere using a60Co gamma source. Some parameters affecting the grafting percentage of this binary mixture have been studied. These parameters include effect of: inhibitor concentration, type of inhibitor, monomer concentrations, monomer composition, and type of solvent. The grafted films were characterized by water uptake, scanning electron microscopy (SEM), contact angle 8, differential scanning calorimetry (DSC), and spectroscopic analysis. 2-Hydroxyethyl methacrylate was found to be more reactive than acrylic acid towards graft copolymerization.