As-cast Mg 17 Al 12 alloy was prepared by induction melting method, and then ball-milled with MgH 2 for 50h to obtain MgH2–10wt% Mg 17 Al 12 composite. The structure and morphology of the composite were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS). XRD results showed that MgH 2 decomposed partly during ball milling. Ball-milled Mg 17 Al 12 alloy could absorb hydrogen at the temperatures over 473K and desorb hydrogen at 613K. The MgH 2 –10wt% Mg 17 Al 12 composite showed rapid H-absorption rate and higher H-capacity with good activation properties, compared with ball-milled MgH 2 . With the increase in hydriding temperature, the maximum hydrogen absorption capacity of MgH2–10wt% Mg 17 Al 12 composite increased from 1.12wt% at 393K to 6.50wt% at 473K. The favorable hydrogenation performance of the MgH 2 –10wt% Mg 17 Al 12 composite was mainly attributed to the synergistic effect of the catalytic efficiency of Mg 17 Al 12 alloy and defects on the surface and/or in the interior of Mg formed during ball milling process.