A series of Zr x Ce 1−x O 2 –Al 2 O 3 (x=0, 0.25, 0.5, 1) nanocomposites were prepared through a citric acid mediated route. The thermal stability of these materials was investigated by calcination at temperatures between 1173 and 1473K for a certain time. The nanocomposites were characterized by XRD, DTA, nitrogen adsorption–desorption measurements, Raman spectroscopy, TEM and SEM. It was found that coating Zr x Ce 1−x O 2 on the surface of Al 2 O 3 could substantially enhance the thermal stability of the composites, as evidenced by preventing the formation of α-Al 2 O 3 . Rh/Zr x Ce 1−x O 2 –Al 2 O 3 catalysts were prepared by incipient wetness impregnation, followed by calcination at 1173K for 5h. The Rh dispersion was measured by volumetric H 2 -chemisorption. The effect of the catalyst support, the reaction temperature, the Rh loading and the gas hourly space velocity in the catalytic partial oxidation of methane was studied in a quartz fixed-bed reactor, concerning activity, selectivity and stability. The ignition and extinction behaviors of the reactor on different catalysts were also investigated showing that the ignition temperature depends significantly on the composition of the supports. It was observed that the presence of cerium in the composites would lower the ignition temperature and enhance the activities of methane partial oxidation and water gas shift reaction.