Composites of [γ-H₂PV₂W₁₀O₄₀]³⁻ and [α-SiW₁₂O₄₀]⁴⁻ supported on Fe₂O₃ (PV2-SiW12/Fe₂O₃, in particular, the molar ratio of PV2/SiW12 = 1/1) could act as effective and reusable heterogeneous catalysts for selective oxidation with aqueous hydrogen peroxide. In the presence of PV2-SiW12/Fe₂O₃, various kinds of organic substrates such as alkenes, sulfides, arenes, and alkanes could selectively be converted into the corresponding oxygenated products in moderate to high yields. The observed catalyses for the present oxidations were intrinsically heterogeneous, and PV2-SiW12/Fe₂O₃ could be reused at least three times for each oxidation (epoxidation, sulfoxidation, and arene hydroxylation) without appreciable losses of the high catalytic performance.