Oxygen vacancy plays an important role in determine the catalytic activity of the supported noble metal catalyst during oxidation process. In this paper, CeO2 nanoparticles, single-crystalline nanorods and nanocubes with different exposed facets were synthesized as support through hydrothermal method. After loaded with Pd species, the structure effect of CeO2 support on CO oxidation process was studied. The experiment clearly shows that Pd loaded on CeO2 nanocubes, which are dominantly exposed by {100} facet, possesses the highest catalytic activity. The 50% CO conversion temperature is about 35 degrees C, much lower than that CeO2 nanorods (60 degrees C) and nanoparticles (90 degrees C), corresponding well with the order of the formation of oxygen vacancy on the different exposed facets of the CeO2 crystalline. (C) 2016 Elsevier B.V. All rights reserved.