In this paper,magnesium-Copper hydrogen storage material (Mg2Cu-H) was prepared with a replacement-diffusion method and its structure was determined by XRD and ICP.Results show that the Mg-Cu hydrogen storage material was a mixture of MgCu2 and MgH2.Hydrogenation reaction time could obviously influence the hydrogenation reaction of Mg2Cu and the purity of Mg2Cu-H.