The homogeneous Mg2Ni1-xCox (x = 0.05, 0.1) compounds were successfully prepared from magnesium, nickel and cobalt ultratine particles, which were obtained from a hydrogen plasma-metal reaction. XRD and TEM results demonstrate that the homogeneous nanostructured Mg2Ni1-xCox with less impurity were successfully synthesized by this method. DSC in hydrogen atmosphere, pressure-composition isotherm and the kinetics of hydrogen adsorption/desorption were investigated. The results show-that the nanostructured Mg2Ni1-xCox compounds present superior sorption kinetics. (c) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.