A novel Bi2WO6@carbon/Fe3O4 nanostructure with a thin carbon interlayer was reported. Reactive carbon interlayer was introduced as a key component for the growth of Bi2WO6 nanoplates on the magnetic Fe3O4 microsphere. After the carbon layer was oxidized by the KMnO4 in the basic solution, Bi3+ ions could be adsorbed by the as produced -COO-groups and thus Bi2WO6 nanoplates grew on the surface of the carbon/Fe3O4 microspheres preferentially. The as-prepared nanocomposite, which could be easily recovered by a magnet, exhibited high efficiency in the photocatalytic decomposition of phenol with the assistance of H2O2. The combination of photocatalyst and magnetic materials through a reactive carbon interlayer opens up a new route for the fabrication of complex and multifunctional nanostructure. (C) 2009 Elsevier B.V. All rights reserved.