Two types of catalysts with the same palladium loading, palladium-substituted perovskite (LaFe0.77Co0.17 Pd0.06O3) and perovskite-supported palladium catalyst (Pd/LaFe0.8Co0.2O3) were prepared, and the effects of the preparation methods and reactant gas composition on the catalytic behaviors were investigated in detail. The catalyst structure was characterized by X-ray diffraction (XRD), transmission electron micrograph (TEM), temperature-programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS) techniques. It was found that the excellent three-way catalytic activities could be obtained under slight rich conditions due to hydrocarbon steam reforming. The activity performance of Pd/LaFe0.8Co0.2O3 was higher than that of LaFe0.77Co0.17Pd0.06O3 and this was owing to the ease of reduction of palladium in the former. (C) 2002 Elsevier Science B.V. All rights reserved.