The hydrogen storage properties of La2Mg16Ni alloy prepared by mechanical milling in benzene or under argon were investigated. The scanning electron microscope results show that there are obvious differences in the surface morphology for different ball milling conditions. Compared with the sample milled under argon, the alloy milled in benzene has relatively faster absorption/desorption kinetics. Furthermore, the milling in benzene destabilizes the alloy hydride. The ball milling in organic solvent offers a new way for magnesium-based hydrogen storage materials, exploiting their higher capacity and higher equilibrium pressure while operating at lower temperature. (C) 2003 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.