Nickel supported gamma-alumina (Ni/gamma-Al2O3) catalysts are well-known to be highly active on the autothermal reforming of methane, but to be unstable due to coke deposition. Cerium oxide (CeO2) is one of promising promoter to overcome the fast deactivation of nickel-based catalysts by coke formation. Herein, catalytic behavior of CeO2 over Ni/gamma-Al2O3 catalysts on the autothermal reforming of methane was investigated. The catalytic activity was maintained for 100 h with H-2/CO molar ratio of 1.9. The formation of CeAlO3 is observed at the reduction and reaction conditions. In this work, it was found that the formation of CeAlO3 promoted the catalytic oxidation toward CO2 and prevented the formation of alpha-Al2O3 and nickel-aluminate, resulting in stable activity for autothermal reforming of methane. Copyright (c) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.