PVA incorporated with different content of CdS-Ag nanostructures were prepared using a chemical reduction technique. Along with this these nanocomposites were exposed to UV radiated for different times. The X-ray spectra of PVA /CdS-Ag nanocomposites indicated the formation of CdS and Ag nanostructures within PVA. Changes in the band structure of nanocomposites with and without UV exposure were studied by UV-Visible spectroscopy. Absorbance and refractive index showed incremental increases with the concentration of nanostructures and time of exposure. In addition, the behaviour of different optical parameters such as E˳ and Ed was investigated. Field-emission scanning electron microscopy and energy-dispersive X-ray analysis showed microstructural modification occurring in the nanocomposites due to changes in the concentration of incorporated nanostructures and UV radiation. The influence of concentration and UV exposure on conductivity and dielectric parameters on PVA/CdS-Ag nanocomposites was studied.