In this study, La-Ce/γ-Al₂O₃ materials for the catalytic ozonation of phenol were prepared by impregnation. In order to analyze the physicochemical properties, BET, SEM, XRD, XPS, and FTIR were used to characterize the catalysts. The removal performance of phenol under different reactive conditions (catalyst dosage, initial pH value, initial phenol concentration, and ozone concentration) was investigated, and the possible catalytic oxidation mechanism and conversion pathway of phenol were proposed through the analysis of ROS and intermediates in solution. The results indicated that the conversion rate of 2.5% La-Ce/γ-Al₂O₃ increased by 20.53% within 20 min compared with ozonation alone. Moreover, the CO₂ mineralization rate was more than twice that of ozonation alone within 250 min, reaching 92.53%, and superior CO2 mineralization was maintained after repeated use. The CO₂ mineralization rate of phenol after adding 3 g/L 2.5% La-Ce/γ-Al₂O₃ catalyst reached almost 100%, and could be maintained in a solution with a wide pH range of 3~9.5. From the characterization results, it could be seen that the 2.5% La-Ce/γ-Al₂O₃ catalyst obtained higher adsorbed oxygen and hydroxyl species content than γ-Al₂O₃ and Ce/γ-Al₂O₃. In the process of phenol catalyzed ozonation, the •O₂ˉ species in the solution were deduced to be the key ROS.