Abstract The aim of this work was to obtain ceria-based catalysts with improved oxidation properties by adding tin dioxide (5, 10 and 20 wt %) and using the co-precipitation method of preparation. The samples were characterized by BET, ESEM, and DRIFT spectroscopy. The activity of SnO2-CeO2 catalytic systems in CO oxidation was studied between room temperature to 673 K. It was found that the increase of SnO2 content obviously increases the low temperature CO conversion. However, at 673 K all the samples reach almost the same conversion of around 98-99%. The surface acidity was studied by NH3 adsorption in order to better understand the mechanism of CO transformation to CO2.