Increasing attention has been devoted to hydrogen production as a source of clean energy that is friendly to the atmosphere. Dry reforming process provides an excellent means for producing hydrogen as well as mitigating CO2 and CH4, greenhouse gases that cause global warming. Catalyst activity and stability depend on the support, active metal and methods of pretreatment. In the present work, the effect of calcination temperature on hydrogen production using cobalt supported over nano-sized ceria and zirconia catalysts was investigated. The catalysts were prepared by the wet impregnation method at different calcination temperatures (i.e., 500, 600, 700, 800 and 900 degrees C). BET, TGA, XRD, TPO, TPR and TEM techniques were used to characterize the prepared catalysts. The results revealed that the catalysts calcined at 500 and 600 degrees C exhibited better activity and higher hydrogen production than those calcined at higher temperatures. The hydrogen yields, for Co/ZrO2 and Co/CeO2 catalysts, calcined at 500 degrees C and 600 degrees C, were 75.8% & 71.4% and 59.4% & 57.5% respectively. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.