Mechanical milling technology was used to treat the cast La1.8Ca0.2Mg16Ni ingot. The milled alloy was analyzed through XRD, TEM, SEM. The alloy was changed from crystalline into amorphous after 40 h of milling. The amorphous La1.8Ca0.2Mg16Ni alloy shows much better desorption kinetics than the crystalline alloy and has a higher hydrogen storage capacity. But the incubation period for hydriding of the alloy increases. Some powder of alloy Mg2Ni was added into La1.8Ca0.2Mg16Ni and grinded together. The amorphous La1.8Ca0.2Mg16Ni + 10 Wt% Mg2Ni alloy shows an improved activation property. (C) 2002 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.