The invention discloses a method for preventing W loss in a WO3-H2O2 catalytic oxidation system. WO3 serves as a W catalyst after being loaded on a solid carrier, the solid carrier refers to aluminosilicate, the W catalyst, hydrogen peroxide and a reaction substrate are mixed evenly and stirred for a reaction, solid is separated out by centrifugation after the reaction, and after being recycled through post-treatment steps, the solid is mixed with hydrogen peroxide and the reaction substrate to repeat the catalysis reaction. The WO3 is loaded on the solid carrier, the carrier simultaneously has the effects of solid acid and solid adsorbents in the reaction process, solid-liquid separation is performed after the reaction, the solid is washed with an ethanol solvent, then dried, recycled andrepeatedly used for catalysis reaction, and it is proved that the catalytic activity is not significantly reduced after repeated use for 10 times. It shows that the method effectively prevents the loss of the W catalyst in the WO3+H2O2 catalytic oxidation system, and the recycled catalyst can be reused.