Ni-CaO-ZrO2 catalysts for CO2 reforming of CH4 were prepared by either co-precipitation or impregnation and characterized by means of N-2 adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature programmed (TP) techniques. It was found that the preparation procedure greatly influenced the physicochemical properties of catalysts, such as morphology, phase and surface structure. As a result, their activity in CO2 reforming of CH4 was determined by the dispersion of Ni and the co-precipitated catalysts showed a better stability. Furthermore, CO2-TPD and transient pulse experiments suggested that the carbon formed over two co-precipitated catalysts was eliminated by different mechanisms, and redox properties and strong basicity were believed to be the key factor for the stability, respectively. (C) 2011 Elsevier B.V. All rights reserved.