The decompositions of lithium amide (LiNH2) and lithium imide (Li2NH) are important steps for hydrogen storage in Li3N. Herein, the decompositions of LiNH2 and Li2NH with and without anion promoter were investigated by using temperature-programmed decomposition (TPD) and X-ray diffraction (XRD) techniques. It was found that the decomposition of LiNH2 produced Li2NH and NH3 via two steps in the temperature range of 300-450 degrees C: LiNH2 into a stable intermediate species (Li1.5NH1.5) and then into Li2NH. Furthermore, Li2NH is decomposed into Li, H-2, and N-2 without formation of Li3N in the temperature range of 550-750 degrees C. The decompositions of LiNH2 and Li2NH can be promoted by chloride ion (Cl-). The introduction of Cl- into LiNH2 resulted in the generation of a new NH3 peak at low temperature of 250 degrees C besides the original NH3 peak at 330 degrees C in its TPD profiles. Furthermore, Cl- can decrease the decomposition temperature of Li2NH by about 110 degrees C.