In this paper, a series of Pt-Ni/CeO2 bimetallic catalysts were prepared by incipient-wetness impregnation with different sizes of the nanospherical cerium oxide that was prepared by hydrothermal crystallization as carrier, and their application in the reaction of ESR (ethanol steam reforming) was investigated.The physical and chemical properties and the reduction properties of the catalysts were analyzed by XRD, SEM, N2 adsorption-desorption and H2-TPR.The in-depth study of the catalytic performance of the catalysts were cauducted.The results show that with 2 Pt-6 Ni/CeO2 (50 nm) as the catalyst, after 10 hof reaction under reaction temperature of 450 ℃ and the molar ratio of water to alcohol 6∶1, the conversion of ethanol did not change obviously, the selectivity of hydrogen remained about 70%, the selectivity of byproduct CO was1.5%, and the presence of trace amounts of acetaldehyde molecules was observed.This can be attributed to the synergistic effect between the Pt and Ni active components.Pt can promote the decomposition and dehydrogenation of ethanol.In addition to its strong C—C bond breaking ability, Ni component also has a definite activity on water gas shift reaction and methane reforming, thus reducing the content of CO and CH4 in the product.Meanwhile, the presence of Pt improves the dispersion of Ni component.In addition, CeO2 with high oxygen activity also promotes the dissociation of ethanol and vapor, overcoming the carbon deposition on the metal surface, and its interaction with Pt and Ni promotes the catalytic performance of the catalyst to some extent.