Ni catalyst supported on ordered mesoporous carbon was prepared by co-precipitation (CP) method and characterized by N2 physical adsorption, XRD, TG-DTG, H2-TPR, H2-TPD and TEM.The property was evaluated by ammonia decomposition and compared to the Ni-base catalysts supported on active carbon and graphite.N2 adsorption-desorption isotherms revealed a mesoporous nanocatalyst system with high surface area and uniform pore size distribution.The catalytic activity measurements showed that the Ni/MC catalyst were very active in ammonia decomposition.The catalytic behavior depends on the small nickel particle size, high dispersion nickel species.