Nanocomposite solutions of polyvinyl pyrrolidone (PVP) embedded with different concentrations of copper oxide (CuO) nanoparticles were prepared to study the CuO effect on a polymer matrix. The obtained solutions were then properly analyzed by Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV-Vis). In the FTIR spectra, the primary distinguishing bands of PVP and CuO were evident. The fact that some bands' strengths dropped indicates that effective reactions were going on between the functional groups inside the PVP and CuO. An optical study revealed that when the Cu+2 ions grew, the film's transmittance and energy band gap shrank. These results imply that the PVP matrix loaded with CuO nanoparticles has suitable structural and optical properties, boosting its potential industrial uses, notably in optical components and devices. Moreover, due to the strong reduction of transmittance to 1%, a PVP/CuO nanocomposite sample with 1.0 wt.% CuO can be used as a blocking material for the UV, visible, and near-IR regions of the electromagnetic spectrum. Theoretical results also indicated that the HOMO/LUMO band gap decreased with CuO filler while total dipole moment (TDM) increased. These findings show how experimental and theoretical work can be combined to gain a better understanding of how molecular structures interact, revealing unexpected properties of nanostructures.