Herein, we report the multi-metal atomic catalysts for solid-state dehydrogenation of MgH. It aims to reveal the multi-element synergy in catalysts for solid-state hydrogen storage. The kinetic measurements and fitting reveal two mechanisms: one shows a maximum rate at the early stage, such as V and Cr; the other needs a temperature-sensitive preparation time for its maximum rate, such as Ni. The combination of two catalyst components demonstrates the best kinetics: V and Cr boost the initial dehydrogenation, and Ni benefits the further hydrogen transfer which alleviates the rate of decay. This work provides guidelines for the design of multi-element doped catalysts for MgH dehydrogenation.