We investigated emission spectrum of LiH molecules from an electric discharge in a heat-pipe oven. The optimal conditions for the most intense LiH emission regarding the vapour pressures of helium, hydrogen and lithium were found to be 2.5 Torr, 8.5 Torr and 0.9 mTorr, respectively. The important role of helium gas in increasing the LiH emission intensity is described. The number density of the lithium atoms in the first excited state, Li(2p) and the LiH emission, was measured for different hydrogen pressures and currents through the discharge. We found that one part of the LiH molecules formed in the discharge is created in chemical quenching of excited lithium atoms by H₂ . We performed the theoretical simulations for observed LiH A ¹ ⁺ -X ¹ ⁺ emission band. The rotational temperature and the population distribution of vibrational levels in the LiH A ¹ ⁺ state were determined. We also describe the search for emission from the LiH C ¹ ⁺ electronic state in the spectrum, which at present is unsuccessful.