A series of CeO₂/g-C₃N₄ composite catalytic materials were prepared by microwave-assisted double template method and soft template method, and the materials were characterized by XRD, N2 adsorption-desorption, XPS, SEM and TEM, and their wet catalytic properties were investigated. The results showed that the D-CeO₂/g-C₃N₄ composites prepared by the double-template method exhibit the characteristics of cubic-phase CeO₂ and laminated g-C₃N₄, with large specific surface area and pore size, which are mesoporous structures and the presence of Ce^₃₊ and Ce^₄₊ on the surface, which are favorable to the formation of oxygen vacancies. The D-CeO₂/g-C₃N₄(7.5) sample obtained after adding 1 g of block copolymer F127, using anhydrous ethanol solution as the solvent and adjusting the mixture to be alkaline, and microwave radiation reaction for 120 min had a complete and homogeneous structure with the best morphological characteristics. The COD removal rate of 100 mg/L phenol solution could reach more than 80% when the reaction temperature was controlled at 75 ℃, D-CeO₂/g-C₃N₄(7.5) was injected at 0.7 g, H₂O₂ was injected at 0.5 mL, and the initial pH was 5. The D-CeO₂/g-C₃N₄(7.5) composite catalytic material could still achieve more than 60% catalytic degradation after five times of use.