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Hexa-spinel ferrite nanoparticles of Cobalt Lead Ferrite (CPFO)were prepared by a flash auto combustion method, while xCPFO/PS (x = 0, 2.5, 5, and 7.5 wt.%) nanocomposite films were synthesized by casting method. The diffraction pattern Rietweld refinement of CPFO nanoparticles confirmed the formation of two phases; face-centered cubic spinel and hexagonal structure. HRTEM micrographs of Cobalt Lead Ferrite (CPFO) nanoparticles shows average particle size around 30 nm. FESEM cross-section images of CPFO/PS nanocomposite films showed CPFO nanoparticles dispersed in PS matrix. All optical characteristics of the synthesized nanocomposite films, including absorbance, transmittance, direct and indirect energy band gap, Urbach energy, excitation coefficient and refractive index were investigated using a UV-visible spectrophotometer examination. The direct optical energy band gap lowered from 4.533 eV to 4.368 eV and the indirect energy optical bandgap lowered from 4.337 eV to 4.146 eV while the Urbach energy raised from 0.103 eV to 0.209 eV with increasing the nanofillers from 0 to 7.5 wt.%. Broad-band dielectric spectroscopy was used through a wide frequency range (0.1Hz-1MHz). The dielectric real permittivity (ε′), the dissipation factor tan (δ) and the electric modulus (M′&M′′) measurements were studied. CPFO nanoparticles addition significantly enhanced the dielectric real permittivity (ε′), the dissipation factor tan (δ) and ac conductivity of all nanocomposites.