A hybrid catalyst based on monoprotonated divanadium-substituted phosphotungstate ([γ-HPV₂W₁₀O₄₀]⁴⁻) was synthesized and used for the selective oxidation of sulfides. The catalytic system was carried out in water with hydrogen peroxide at room temperature. Unprecedented turnover numbers (TONs) for all substrates were obtained, which are much higher than previous reports.