The decomposition of lithium imide (Li2NH) is an important step for hydrogen storage in Li3N. In this paper, the decomposition of Li2NH was investigated by using temperature-programmed decomposition (TPD) and X-ray diffraction (XRD) techniques. It was found that the decomposition of Li2NH produced Li, N-2 and H-2 via two steps: Li2NH into an intermediate species-Li4NH and then into Li. The kinetic analysis of Li2NH decomposition showed that the activation energies are 533.6 kJ/mol for the first step and 754.2 kJ/mol for the second step. Furthermore, XRD demonstrated that the Li4NH, which was generated in the decomposition of Li2NH, formed a solid solution with Li2NH. In the solid solution, Li4NH possesses a similar cubic structure as Li2NH. The lattice parameter of the cubic Li4NH is 0.5033 nm. Copyright (c) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.