Ultraviolet radiation (UV) absorption- ability of poly (vinylpyrrolidone-g-acrylonitrile) blend and the effect of adsorption of UV-absorbers into the polymeric substrate were discussed in chemical interaction between UV-absorbers and poly (vinylpyrrolidone-g-acrylonitrile) blend as a substrate. The blend has chemical groups to interact with UV absorbers and has high visible transparency and radiation-durability. The results showed that the chemical and molecular structural character of UV absorber and of polymeric substrate affects sensitively the absorptionability of UV radiation and the adsorption-ability of UV-absorber into its substrate materials. The interaction system of 2- or 4-hydroxy in benzenoid with carbonyl in phenone or pyrrolidone was mainly investigated by UV spectrometer and FT-IR spectrometer. The blend prepared under proper constituent and condition shows excellent UV-shielding property.