<p>Three nanocomposite films from the polyvinyl butyral (PVB) and Cu, Sn, and (Sn/Cu) were prepared utilizing the solution casting technique. The purpose of this study is to uncover influence of nanoparticles such as Cu, Sn, and (Sn/Cu) into structure and linear/nonlinear optical properties of nanocomposite films. Outcome nanocomposite films were identified via FTIR, XRD, SEM, TEM. Results cobfirmed the formation of nanoparticles from Sn, Cu, and (Sn/Cu) were formed into materix of PVB. FTIR showed that peaks of PVB were shifted noticeably compared to the neat PVB film. Results referred to the average particle size of Sn, Cu, and (Sn/Cu) were 15.7 ± 6.7, 18.2 ± 7.4, and 72.5 ± 13.5 nm, accordingly. The direct optical band gap energy of the PVB film was reduced from 5.84 eV to 5.45, 4.64, and 4.60 eV after adding Cu-NPs, Sn-NPs, and Sn/Cu-NPs, respectively. Conversely, the films’ band tail and carbon clusters were augmented after adding Cu-NPs, Sn-NPs, and Cu/Sn-NPs to the PVB matrix. Furthermore, results exposed the induced of Cu-NPs, Cu-NPs, and Sn/Cu-NPs on some optical features of PVB such as refractive index (<i>n</i>), dielectric constant (<i>ε</i>), and extinction coefficient (<i>K</i>). Incorporation of diverse nanoparticles also signifcantly affect optical conductivity (<i>σ</i>_<i>opt</i>), oscillation energy (<i>E</i>_<i>o</i>), dispersion energy (<i>E</i>_<i>d</i>), and average oscillator wavelength (λ_o). The studies were also executed on the susceptibility of non-linear optical and non-linear refractive index. Results confirm that adding Cu-NPs, Sn-NPs, and Cu/Sn-NPs to the PVB improves its nonlinear and linear optical properties. This renders nanocomposite films more useful for applications such as flexible electronic, nonlinear optics, and optical devices.</p>