Abstract: A low-temperature and high-efficiency ammonia decomposition catalyst is disclosed, which includes a support and an active component. The support is SBA-15/G and the active component is nickel. The preparation method of the low-temperature and high-efficiency ammonia decomposition catalyst includes the following steps. Ni(OH)2 is mixed with SBA-15/G composite support by simple mechanical mixing method. Then, Ni/SBA-15/G supported catalyst is prepared by calcination in ammonia atmosphere. The ammonia decomposition activity of prepared materials at low-temperature is higher than that of most current Ni-based catalysts, and the method has the advantages of simple preparation process and low cost, and exhibits high catalytic activity and stability in the ammonia decomposition reaction.