In this study, a series of Ce-OMS-2 catalysts were synthesized by a hydrothermal method, their phys-icochemical properties and catalytic activity for ozone decomposition were evaluated. The results show that suitable grain size and morphology can be formed as needed by tuning the hydrothermal conditions. In this way, the content of surface oxygen in the catalyst can be increased to enhance the reduction performance of the samples. At the same time, the quantity of low-valent manganese (Mn2+ and Mr(3+)) can be increased to raise the oxygen vacancy concentration, and finally improve the O-3 elimination performance of the catalyst. On the basis of this study, we screened out a suitable range of hydrothermal conditions, namely 95-100 degrees C and 8-24 h, which showed a higher ozone conversion rate than manganese oxide catalysts reported to date. The durability of the preferred catalyst under harsh conditions shows that preferred Ce-OMS-2 catalysts can meet the requirements of engineering applications.