Chemical coprecipitation methodology in atmospheric air has been used to prepare Zinc sulfide (ZnS) nanoparticles (NPs); EDTA-ethylenediamine was used as stabilizing agent. Then ex-situ casting technique was used to synthesis nanocomposite (NCP) from Polycarbonate polymer (PC) and the synthesized ZnS NPs. Rietveld enhancement of XRD records demonstrated that synthesized ZnS adjusts cubic zinc blend construction of lattice constant matches 5.345 Å and an average grain size 4nm. PC/ZnS NCP samples were irradiated with doses in the range 25-230 kGy. The modifications in optical parameters of the irradiated NCP samples were investigated using UV spectroscopic analysis and CIE color variation technique. Tauc’s model and optical dielectric loss assisted in estimating the optical band gap (Eg) and to recognize the type of electronic transition. Eg decreased from 3.83 to 3.00 eV upon increasing the doses up to 230 kGy; demonstrating the enhancement of the amorphous phase in the NCP. This was conveyed by an increase in the refractive index. Moreover, the color variations were explored using UV transmission spectra and the CIELAB color space methodology. The radiation causes a reduction in green and blue color components, conveyed by an increase in whiteness. This led to a noteworthy color variation that is applicable in marketable imitation on printing press.