This study investigates the synthesis and characterization of Fe3O4-CdO nanocomposites for the photocatalytic degradation of Methylene Blue (MB) dye. The nanocomposites were prepared using a solution combustion method with cetyltrimethylammonium bromide (CTAB) as a template. Characterization techniques, including X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron microscopy (XPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), were employed to analyze the samples. XRD confirmed the crystalline nature and purity of the samples, while UV-vis DRS studies revealed the optical properties and bandgap energy. FTIR and Raman spectra indicated the formation of metal-oxygen bonds. TEM and SEM analyses determined the surface morphology and size of the nanoparticles. Under visible light irradiation, the Fe3O4-CdO nanocomposites showed efficient photocatalytic degradation of MB dye, achieving a 92% degradation rate and demonstrating excellent stability for multiple reuse cycles. The study highlights the potential of Fe3O4-CdO nanocomposites as effective photocatalysts for environmental remediation.This study investigates the synthesis and characterization of Fe3O4-CdO nanocomposites for the photocatalytic degradation of Methylene Blue (MB) dye. The nanocomposites were prepared using a solution combustion method with cetyltrimethylammonium bromide (CTAB) as a template. Characterization techniques, including X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron microscopy (XPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), were employed to analyze the samples. XRD confirmed the crystalline nature and purity of the samples, while UV-vis DRS studies revealed the optical properties and bandgap energy. FTIR and Raman spectra indicated the formation of metal-oxygen bonds. TEM and SEM analyses determined the surface morphology and size of the nanoparticles. Under visible light irradiation, the Fe3O4-CdO nanocomposites showed efficient photocatalytic degradation of MB dye, achieving a 92% degradation rate and demonstrating excellent stability for multiple reuse cycles. The study highlights the potential of Fe3O4-CdO nanocomposites as effective photocatalysts for environmental remediation.