We used casting method to create nanocomposites films from carboxymethylcellulose (CMC)/polyvinyl alcohol (PVA) and GO/Fe3O4 as nanofiller. Various analyses such as structural, vibrational, optical, conductivity, dielectric and magnetic studies reveal promising properties of the prepared polymer nanocomposites (PNCs) films. The amorphous phase of the polymer blend increased with increasing GO/Fe3O4 concentration up to samples containing 0.05%GO/1%Fe3O4 nanofiller, according to X-ray diffraction. The complexation of the nanofiller with the polymer blend's –OH, –COO, CO, and –CH groups through a coordinate bond/hydrogen bond was confirmed by Fourier-transform infrared analysis. While the Urbach energy showed a trend in the opposite direction, the optical bandgap gradually turned red as the nanofiller concentration increased. The interaction of GO/Fe3O4 ions with the CMC/PVA matrix is attributed to the changes in optical properties of CMC/PVA. The Jonscher's power law (JPL) is observed in all samples' ac conductivity spectra. To comprehend the charge storage competences, research of dielectric permittivity was also conducted. A study of dielectric permittivity was also conducted to comprehend the charge storage competences. While AC conductivity increases with frequency, dielectric characteristics decrease with frequency. With the addition of nanofiller, AC conductivity and dielectric characteristics increase. For 0.05%GO/1%Fe3O4 nanofiller loaded sample, the highest AC conductivity and dielectric constant were attained. The results of vibrating sample magnetometer (VSM) revealed that synthesized nanocomposite films exhibit superparamagnetic features. The unique features of CMC/PVA-GO/Fe3O4 films enable their employment in a variety of industries, including magnetic electronics, energy storage devices, and optoelectronics.