A series of composite catalysts Ni/CeO2-ZrO2 were prepared via impregnation method with Ni as the active metal. A laboratory-scale fixed-bed reactor was employed to investigate the catalyst performance during hydrogen production by steam reforming bio-oil aqueous fraction. Effects of water-to-bio-oil ratio (W/B), reaction temperature, and the loaded weight of Ni and Ce on the hydrogen production performance of Nil CeO2-ZrO2 catalysts were examined. The obtained results were compared with commercial nickel-based catalysts (Z417). The best performance of Ni/CeO2-ZrO2 catalyst was observed when the Ni and Ce loaded weight were 12% and 7.5% respectively. At W/B = 4.9, T = 800 degrees C, H-2 yield reaches the highest of 69.7% and H-2 content of 61.8% were obtained. Under the same condition, H-2 yield and H-2 content were higher than commercial nickel-based catalysts (Z417). (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.