3D spherical Cr-Ce mixed oxides were successfully synthesized via the hydrothermal method in different solvents, and their efficiencies of catalytic oxidation NO were evaluated. Among all catalysts, CrCeEt (ethanol adopted as the solvent) exhibited the best low-temperature catalytic NO oxidation performance, which was over 40% at 200 degrees C and reached 50% at 230 degrees C. The high activity at low temperature could be ascribed to the particle size and roughness on the surface, which could make the surface with active site more exposed, thus enhancing the catalytic performance at low temperature. Further, the exposed surface could generate more Cr6+ and O-beta ratios, which played the key role in NO oxidation. Moreover, CrCeEt catalyst exhibited the stable catalytic performance and the strong H2O(g) resistance, promoting the industrial application of new SCO technique, which the denitration system was placed after the desulfurization system.