Using the density functional theory with the generalized gradient approximation, we have examined the adsorption and dissociation of H-2 on cluster Al6Si. The stable geometrical structures of both the reactants and the products, the transition states, and the reaction paths for the dissociations are investigated. The results show that the adsorption energies of H-2@Al6Si are small, which implies they are not suitable for storing H-2 directly. However, the energy barrier for each reaction is found in the range of 0.437-1.154 eV, implicating that Al6Si can store hydrogen with dissociating the H-2 into separate atoms. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.