Palladium catalysts supported on mixed oxides (Pd/Al2O3-MOx; M=Co, Cr, Cu, Fe, Mn, and Ni) were investigated for the low-temperature catalytic combustion of methane. Although the surface area decreased with increasing NiO in Pd/mAl(2)O(3)-nNiO, Pd/Al2O3-36NiO demonstrated an excellent activity due to the small particle size of palladium. Also, the catalytic activity strongly depended on the composition of the support. Temperature-programmed desorption of oxygen revealed that the catalytic activity in the low-temperature region depends on the adsorption state of oxygen on palladium. The activity was enhanced when the amount of adsorbed oxygen increased. In-situ XRD analysis indicated that the PdO phase was thermally stabilized on Pd/Al2O3-36NiO.