LiAlH4 holds great promise for reversible hydrogen storage, where a fundamental understanding of hydrogen interaction with the metal elements is essential to further improve its proper-ties. The present paper reports a first-principles study of its stability and electronic structure, using a full potential linearized augmented plane wave (FLAPW) method within the generalized gradient approximation (GGA) for high accuracy. The theoretically calculated heat of formation agrees well with experiment. The electronic structures show that the H atoms bond nonequivalently with the Al in the [AlH4](-) ligand, which leads to complex dehydrogenation characteristics of LiAlH4.