CeO2 modified ultrastable Y zeolite (CeO2-USY) catalysts were prepared and were used as the catalysts for the decomposition of 1,2-dichloroethane (DCE). The catalytic behavior of these catalysts was evaluated by micro-reaction and temperature-programmed surface reaction (TPSR) technique. The results reveal that CeO2-USY catalysts exhibit good catalytic activity for DCE decomposition and high selectivity to the formation of CO2 and HCl. Both acidity and redox property play important roles in the DCE decomposition, and the synergy between CeO2 species and USY zeolite shows an enhancement in the catalytic activity for DCE decomposition. CeO2-USY (1:8) with high dispersion of CeO2 species and a much more suitable combination of acidity and redox property exhibits the best catalytic activity. Crown Copyright (c) 2010 Published by Elsevier B.V. All rights reserved.