AbstractNi/CeO2-ZrO2 catalysts were prepared via co-precipitation and characterized by N2 adsorption–desorption, XRD, SEM, and TPR techniques. The effects of reaction temperature, carbon-equivalent space velocity (GC1HSV), and steam-to-carbon ratio (S/C) on the performance of the catalysts for ethanol steam reforming (ESR) were investigated. It was found that the best catalytic performance was obtained over the Ni/Ce0.75Zr0.25 catalyst with GC1HSV=345 h-1 and S/C=9.2. Under these conditions, H2 selectivity reached its highest value of 98% at T=725 °C, and carbon conversion reached 100% at T=825 °C. The performances of Ni/Ce0.75Zr0.25 and Ni/Ce0.5Zr0.5 were also compared at S/C ranging from 2.5 to 9.2. The results showed a higher carbon conversion for the Ni/Ce0.75Zr0.25 catalyst than for Ni/Ce0.5Zr0.5.