Nickel copper ferrite nanoparticles (NPs) in the form Ni0.65Cu0.35Fe2O4 were synthesized by the sol-gel method while PVA-CMC blend films were manufactured by cast method. The prepared films of PVA-CMC/(Ni0.65Cu0.35Fe2O4)x, where x = 2,4,6, and 8 wt%, were characterized using X-ray diffractometer (XRD) and Raman spectroscopy. The transmission and absorption spectra were investigated for PVA-CMC/Ni0.65Cu0.35Fe2O4 films using UV-visible spectrophotometer. The assessment of dielectric characteristics of the prepared PVA-CMC blend films was done by using broadband dielectric spectroscopy (BDS). XRD verified the production of face-centered cubic spinel structure of space group Fd3m with the lattice parameters a = 8.3310 angstrom for Ni0.65Cu0.35Fe2O4 NPs and the amorphous characteristics of blend films. Furthermore, XRD verified that Ni0.65Cu0.35Fe2O4 NPs were included in the blend matrix. The Raman spectra of the PVA-CMC blend films showed several strong characteristic scattering peaks. The optical bandgaps were evaluated via the Tauc's model. The optical bandgap decreases from 5.50 to 5.05 eV and the Urbach energy increases from 1.35 to 2.99 eV, gradually, with increasing NPs' concentrations. Moreover, the index of refraction rises from 1.776 (pure PVA-CMC) to 2.881 (PVA-CMC/8%Ni0.65Cu0.35Fe2O4). Also, it was discovered that as Ni0.65Cu0.35Fe2O4 NPs were added to the PVA-CMC blend matrix, optical conductivity increased as well. The results showed that the PVA/CMC blend films can be tailored by Ni0.65Cu0.35Fe2O4 additives which nominate it for optical devices applications. Three remarkable trends were investigated on the dielectric spectra of the investigated samples. The low frequency range shows a linear increase with decreasing frequency indicating the transport of the free charge carriers. Nano-confinement phenomenon affected in reducing the conductivity of the blend, even the conductivity of the nano-ferrite is higher in conductivity than the blend.