CuMgLa/γ-Al2O3 catalyst was prepared by the co-precipitation method and evaluated by phenol degradation. When catalyst dosage was 0.2 g/L, reaction temperature was 180 ℃, reaction pressure was 1.8 MPa, and stirring speed was 500 r/min, 2 000 mg/L phenol could be completely removed, and COD removal could reach 90.65% in 120 minutes. The catalysts were analyzed by XRD, XPS, NH3-TPD, and TG-DTA. It's found that the average particle size of CuO decreased from 51 nm to 37 nm and 25 nm with the addition of Mg and La, respectively, indicating that CuO on CuMgLa/γ-Al2O3 had a better dispersion and provided more reaction sites. Moreover, introduction of Mg and La into Cu/γ-Al2O3 could weaken the strong acid sites of Cu/γ-Al2O3, thus reducing carbon deposition during phenol degradation.