In this study, polyvinyl alcohol (PVA) was mixed with concentration of 5%, 7.5%, and 10% of manganese dioxide ( MnO2) to form PVA/MnO2 films using solution cast approach method. The X-ray diffraction (XRD) verified that the nanomaterials films were successfully fabricated. The scanning electron microscope (SEM) illustrates the uniform MnO2 dispersion within the PVA host matrix. Additionally, the influence of MnO2 on the optical properties is recorded. The refractive index (n0) is improved by adding MnO2, from 1.29 for PVA to 1.87 for PVA/5%MnO2 and 2.86 for PVA/10%MnO2. The PVA had a dispersion energy of 2.53 eV, while PVA with 5% MnO2 had 4.86 eV, PVA with 7.5% MnO2 had 5.74 eV, and PVA with 10%MnO2 had 7.12 eV. In addition, the oscillation energy E0 decreased from 3.79 for PVA to 1.94, 1.72, and 0.99 eV, respectively for PVA/5%MnO2, PVA/7.5%MnO2, and PVA/10%MnO2. It is evident from the data that the incorporation of MnO2 to the PVA polymer alters its optical properties. This proved the existence of strong interactions of PVA and MnO2 due to the modification of the PVA/MnO2 electronic structure. Moreover, the plasma frequency W p value increased from 0.79 × 1013 s− 1 for PVA to 2.06 × 1013 s− 1 for PVA/10%MnO2. These shifts in W p provided the polarization is modified for the PVA/MnO2. The results obtained in this study provide evidence of the advantages associated with the utilization of MnO2 nanoparticles as a filler of improved polymeric structures. These findings also propose the potential suitability of MnO2 nanoparticles for application in the field of optics and electronic devices.