With plane-wave pseudo-potential method of first-principles,effect of dopant Fe on dehydrogenation characteristics of LiAlH₄ and mechanism were studied.Dopant formation energy,electronic density of states and dissociation energy of H were investigated.Bonding state and structure-stability of the crystal were analyzed.It indicates that as Fe occupied an interstitial site,an Al site or an Li site,dehydrogenation properties of LiAlH₄ were improved.Fe tended to occupy the interstitial site.Analysis on electronic structure reveals that there exist strong interactions between a dopant Fe and its nearest neighbouring Al atoms as Fe occupied an interstitial site.Meanwhile,interaction between a dopant Fe and its nearest neighbouring H atoms is also considerably strong.Stability of the [AIH₄] ligand is distorted.Therefore,dehydrogenation properties of LiAlH₄ are improved.In general,dopant Fe improve dehydrogenation properties of LiAlH₄,which is consistent with experimental observations.