This paper outlines the process of creating polyvinyl alcohol (PVA) composites by adding different amounts (0, 1, 2, 3, and 4) of Y2O3 and SrCO3 nanoparticles (NPs) by the solution casting method. The OM pictures demonstrated the emergence of interconnected pathways inside the polymeric matrix as electrically charged particles, which intensified with greater concentrations of nanoparticles. The structural features of the nanocomposite were analyzed using Fourier transformation spectroscopy (FTIR) to obtain information on molecular vibration. FTIR analysis revealed that the polymer matrix exhibited interactions with the added Y2O3 and SrCO3 nanoparticles. The FTIR analysis has shown the existence of physical interactions between Y2O3 and SrCO3 nanoparticles and the PVA polymer matrix. The nanocomposite surface was analyzed using Field Emission Scanning Electron Microscopy (FESEM). It was discovered that the Y2O3 and SrCO3 nanoparticles were evenly and uniformly dispersed throughout the PVA polymer matrix. An increase in the ratio of Y2O3 and SrCO3 nanoparticles in the PVA led to an increase in absorbance, absorption coefficient, refractive index, extinction coefficient, real and energy band gap. However, the transmittance and indirect energy gap decreased. The absorbance coefficient is below 10(4) cm(-1), indicating an occurrence of indirect electron transition. Finally, the PVA/Y2O3/SrCO3 nanocomposites were tested for the antibacterial against both gram positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli). The result obtained that the inhibition zone diameter increased with increasing Y2O3 and SrCO3 NPs. The PVA/Y2O3/SrCO3 nanocomposite exhibited antibacterial activity.