The present theoretical work deals with thermodynamic analysis based on Gibbs energy minimization method combined with a statistical approach: response surface methodology. By combining these two methodologies, the conditions of optimal operation were obtained. This study brings a novel methodology for thermodynamic analyses, which are normally based only on the Gibbs energy minimization method. Thermodynamic analysis of carbon dioxide reforming of methane has been investigated by method of Gibbs free energy minimization for production of desirable products at a wide range of temperature (600-1300 K), pressure (1-20 bar) and carbon dioxide to methane ratio (0.5-3). Moreover, the surface response methodology was used to determine the cubic polynomial models for mole fraction of hydrogen, carbon monoxide and ratio of H-2/CO based on temperature, pressure and carbon dioxide to methane ratio. Numerical optimization was employed for determining the maximum production of hydrogen while keeping the production of carbon dioxide, methane and carbon monoxide to a minimum; in addition, the optimum ratio of hydrogen to carbon monoxide (1-3) occurs at 1 bar, 1011.99 K and carbon dioxide to methane ratio of 0.5. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.