The influence of the ceria catalysts preparation method on their structure and activity in water gas shift reaction has been studied. Ceria supports were prepared by the precipitation method from aqueous and organic solutions (e.g. alcohols) and the impregnation method used for active metal loading. Ceria catalysts were also prepared, by the coprecipitation method for total concentration of nitrate salts ranging from 0.006 to 0.18 mol/L. All catalysts were tested under conditions of the water gas shift (WGS) reaction. The catalysts were characterized by BET, XRD and SEM analyses and their activities were tested in a flow reactor in the temperature range of 150-350 degrees C with gas hourly space velocity (GHSV) in the range of 750-16,000 h(-1). The catalysts prepared by the coprecipitation method present the highest activity. (c) 2006 Elsevier B.V. All rights reserved.