Oxidation of sulfides, acetylation of alcohols and phenols and selective trimethylsilylation of primary and secondary benzyl alcohols are carried out using silica sulfuric acid-coated Fe3O4 magnetic nanoparticles (SSA@MNPs) as a stable, efficient and magnetically recoverable nanocatalyst. Also, deprotection of silyl ethers was reported in ethanol at room temperature in the presence of SSA@MNPs as a magnetic nanocatalyst. The magnetic nanocatalyst was characterized by FT-IR spectroscopy, TGA, XRD and SEM techniques. The catalyst was easily separated with the assistance of an external magnetic field from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency.