The catalytic activity of Ce1-xNi O-x(2) samples (x = 0.05; 0.10; 0.20) prepared by combustion synthesis have been evaluated in the Oxidative Steam Reforming of C3H8. The high activity and stability of Ce0.95Ni0.05O2 and Ce0.90Ni0.10O2 samples was ascribed to the co-existence of different Ni species: metallic, NiO highly dispersed and Ni2+ ions incorporated into CeO2.