Water constitutes ≈70–90% of the organism's body by mass and is highly important for its survival. Water contains a variety of chemical contaminants introduced by various sectors, resulting in contamination that has a direct impact on the ecosystem. Various approaches are in practice to tackle these issues. Among these, semiconductor photocatalysis appears to be the cutting‐edge technology for the degradation of wastewater contaminants. Herein, the fabrication of Fe3O4−SiO2 nanocomposite via facile co‐precipitation and Stober methods are reported. Various characterization techniques are employed for the structural elucidation, morphology, crystallinity, and stability of the as‐prepared composite. The nanocomposite is employed in catalytic and photocatalytic applications toward the removal of methylene blue (MB) and methyl orange (MO) dyes from a comparative perspective. It is observed that the composite can remove about 93% of MB and 51% of MO within 7 and 6 h, respectively. These findings indicate that the nanocomposite has a higher MB removal effectiveness than the MO. This trend can be accredited to the difference in the chemical structure of both dyes. The nanocomposite is also evaluated for antioxidant and antileishmanial activity, and it is shown to be quite effective even at very low concentrations. Water contains a variety of chemical contaminants introduced by various sectors, resulting in contamination that has a direct impact on the ecosystem. Herein, the fabrication of Fe3O4−SiO2 nanocomposite via facile co‐precipitation and Stober methods is reported, for the catalytic and photocatalytic applications toward the removal of methylene blue (MB) and methyl orange (MO) dyes from a comparative perspective.