In this paper, CeO₂/Fe₃O₄ nanocomposites as magnetically recoverable photocatalysts were synthesized via Fe₃O₄ covering the surface of CeO₂ by a hydrothermal method, to form a flower-shaped photon-Fenton catalyst with a larger specific surface area. The composition, morphology and physicochemical properties of the materials were characterized. It was found that the mesoporous CeO₂/Fe₃O₄ composite material as an adsorbent, photocatalytic and Fenton-like catalyst largely overcomes the limitations of the oxidation properties of CeO₂ and has multiple effects on the removal of Congo red (CR). The superior adsorption capacity of mesoporous materials is attributed to the abundant oxygen vacancies on the surface of CeO₂ and the high specific surface area. In the photo-Fenton reaction process, photocatalysis and Fenton reaction have a synergistic effect, which greatly improves the photocatalytic performance of CeO₂/Fe₃O₄ and has a strong photodegradation ability to pollutants. Moreover, the degradation of CR was enhanced in the presence of hydrogen peroxide (H₂O₂) by the synergistic effect of Fe and Ce valence changes. Flower-shaped photon-Fenton catalyst CeO₂/Fe₃O₄ has a good degradation effect on high concentration CR. Under the optimal conditions of pH 4, H₂O₂ 3.75 ml/L, and catalyst 1.0 g/L, the removal rate of CR 1000 mg/L can reach 82% in 120 minutes. After the degradation reaction, the CeO₂/Fe₃O₄ catalyst was recovered from the reaction mixture using an external magnet and successively used for five consecutive cycles with a considerable catalytic activity which is comparable to the first time was obtained.