This article has attempted to establish eco-friendly organic PVA/Al2O3 nanocomposite membranes and estimate the effectiveness of different additives (1, 2, and 3 wt%) of alumina (Al2O3) nano-filler in PVA matrix on their structural and optical properties for establishing their suitability in photonic applications. Al2O3 nano-filler dispersed in the PVA matrix has been synthesized via the solvent casting technique. The structure of synthesized PVA/Al2O3 nanocomposite membranes has been characterized by Fourier transform-infrared (FTIR), Raman spectroscopy, and X-ray diffraction (XRD). Upon introducing the Al2O3 nano-filler in the PVA matrix, the self-hydrogen bonding between the PVA chains was weakened while hydrogen bonding with Al2O3 was generated. In addition, optical, dielectric, and dispersion analysis suggested that even though the Al2O3 nano-filler in PVA/Al2O3 nanocomposite membranes aided in regularly folding the PVA polymer chains. Moreover, formed new structural defects, disorders, and impurities can be used for tuning the PVA/Al2O3 nanocomposites for optoelectronic applications and for making efficient absorbents for environmental treatments.