<p>In the current work, films of PS/SiO₂–CeO₂ futuristic nanocomposites were fabricated to apply in numerous nanoelectronics, energy storage and biomedical fields. The microstructure, morphological and dielectric features of PS/SiO₂–CeO₂ films were investigated. The obtained results showed that the dielectric constant increased from 3.13 to 3.94 with the increase of (SiO₂–CeO₂) NPs content at 100 Hz and its decreased with the increase of frequency, while the electrical conductivity was increased to 1.53E-11 S/cm with the increase of (SiO₂–CeO₂) NPs content at 100 Hz and its increased with the increase of frequency. These results are welcomed in many energy storage and nanoelectronic applications The antibacterial application of PS/SiO₂–CeO₂ nanocomposites were tested against both Gram-positive(Staphylococcus aureus) and Gram-negative (Escherichia coli). The obtained result was that the diameter of the inhibition zone was increased with the increase of (SiO₂–CeO₂) NPs content. Finally, the PS/SiO₂–CeO₂ nanocomposite showed excellent dielectric properties and high activity for antibacterial compared with other nanocomposites which make them as promising materials for energy storage and biomedical fields.</p>