<p>In this work, nanostructures of silicon carbide (SiC)/iron oxide (Fe₃O₄) doped with poly methyl methacrylate (PMMA) were prepared, and then the polymer nanocomposites were coated with a metal layer of aluminum (Al) to improve the structural and optical properties to be used for optoelectronics fields with low cost and good mechanical properties compared to other nanostructures. The structural and optical properties of PMMA-Fe₃O₄-SiC/Al nanocomposites were studied. The results obtained indicate that at the wavelength of 300 nm, the absorption of poly methyl methacrylate (PMMA) increased by about 56.1% while the transmittance decreased by about 50.9% when the ratio of SiC-Fe₃O₄/Al NPs increased to 3wt%. The energy gap of PMMA decreased from 3.3 to 2.0 eV when the content of Fe₃O₄-SiC/Al NPS nanoparticles reached 3 wt%. At 300nm wavelength, the refractive index increased from 2.15 to 2.62. While the optical conductivity at the same wavelength increased from 2.02 to 3.33 s⁻¹. Other optical constants were improved. These results for the polymer nanocomposites can be a key to their use in the optical and electronics fields. Various devices with excellent structural and optical properties can be manufactured. Finally, the PMMA-Fe₃O₄-SiC/Al nanostructures can be considered promising nanostructures for electronic and optical nanodevices.</p>