The effect of ceria in cobalt-ceria-alumina catalyst was studied using in situ X-ray near edge spectroscopy (XANES) at Co K-edge and Ce L-III-edge. The introduction of ceria in this catalyst resulted in a significant removal of Co from CoAl2O4 spinel phase to Co and COO phases. The Co K-edge revealed the symmetry changes in Co according to the temperature and atmosphere in reduction process. We also showed the stability of Co sites as well the oxidation state of ceria in operando steam reforming of ethanol (SRE) reaction. After reduction of Ce4+ to Ce3+, no significant changes were observed by XANES. Gas Chromatography (GC) analysis showed a high ethanol conversion at 500 degrees C, high hydrogen yield and low formation of undesired products as methane and ethylene. The results showed a Co/Ce/Al2O3 catalyst as promising material to be applied in hydrogen production in SRE reaction. (C) 2016 Elsevier B.V. All rights reserved.