The Ce0.5Zr0.3Al0.2O1.9/Pd-gamma-Al2O3 catalyst prepared by a mechanochemical route and calcined at 1000 *C for 20 h in air atmosphere to evaluate the thermal stability. The prepared Ce0.5Zr0.3Al0.2O1.9/Pd-gamma-Al2O3 catalyst was characterized for the oxygen storage capacity (OSC) and CO oxidation activity in automotive catalysis. For the characterization, X-ray diffraction, transmission electron microscopy and the Brunauer-Emmet-Teller (BET) technique were employed. The OSC values of all samples were measured at 600 degrees C using thermogravimetric-differential thermal analysis. Ce0.5Zr0.3Al0.2O1.9/Pd-gamma-Al2O3 catalyst calcined at 1000 degrees C for 20h with a BET surface area of 41 m(2) g(-1) exhibited the considerably high OSC of 583 mu mol-O g(-1) and good OSC performance stability. The same synthesis route was employed for the preparation of the CeO2/Pd-gamma-Al2O3 and Ce0.5Zr0.5O2/Pd-gamma-Al2O3 for comparison. (C) 2013 Elsevier Ltd. All rights reserved.