A catalyst, as a kind of function material, plays important roles. In the paper RuO2/g-Al2O3 and RuO2-TiO2/g-Al2O3 catalyst were prepared by the impregnation method. The structure o f two catalysts was studied with XRD, SEM and XPS. The addition of TiO2 promoted the dispersion of Ru particles, and made the amount of the chemisorbed oxygen increased on catalyst surface. The activity was investigated in WAO of phenol over RuO2/g-Al2O3 and RuO2-TiO2/g-Al2O3 catalysts. The results showed that two catalysts had good activity, and TiO2 effectively increased the activity of RuO2/g-Al2O3 catalyst in WAO of phenol. With RuO2-TiO2/g-Al2O3 catalyst 96% phenol removal was observed at 150°C and 3MPa after 80min reaction in WAO of phenol.