In situ high-pressure Raman spectroscopy studies on LiNH2 (lithium amide) have been performed at pressures up to 25 GPa. The pressure-induced changes in the Raman spectra of LiNH2 indicates a phase transition that begins at similar to 12 GPa is complete at similar to 14 GPa from ambient-pressure alpha-LiNH2 (tetragonal, M) to a high-pressure phase denoted here as beta-LiNH2. This phase transition is reversible upon decompression with the recovery of the (alpha-LiNH2 phase at similar to 8 GPa. The N-H internal stretching modes (v([NH2](-))) display an increase in frequency with pressure, and a new stretching mode corresponding to high-pressure beta-LiNH2 phase appears at similar to 12.5 GPa. Beyond similar to 14 GPa, the N-H stretching modes settle into two shouldered peaks at lower frequencies. The lattice modes show rich pressure dependence exhibiting multiple splitting and become well-resolved at pressures above similar to 14 GPa. This is indicative of orientational ordering [NH2](-) ions in the lattice of the high-pressure beta-LiNH2 phase.