The SiO2 and Ni-SiO2 were synthesized via the complex-decomposition method by using different organic acids as the complexing agent and fuel. The Ni-supported SiO2 from different sources was prepared by the incipient impregnation method. The Ni-SiO2 and Ni/SiO2 were comparatively evaluated for carbon dioxide reforming of methane (CDR) under severe conditions of CH4/CO2 = 1.0, T = 750 degrees C, GHSV = 53200 mL g(-1) h(-1), and P = 0.1 - 1.0 MPa. The materials were fully characterized by XRD, XPS, TEM, TG-DSC, H-2-TPR, and N-2 adsorption-desorption at 196 degrees C. It was found that the complexing agent and preparation method of the catalyst significantly affected its surface area, the size and dispersion of Ni, the reduction behavior, and the coking and sintering properties, which determine the activity and stability of the catalyst for CDR. As a result, a highly active and stable Ni-SiO2 for pressurized CDR was obtained by optimizing the complexing agent. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.