Infrared spectroscopy of molten LiCl-KCl-LiH at 673 K provided absorption band in the wavenumber region of 1400-1500 cm(-1) for several H- ion concentrations. This absorption band is ascribed to the vibration of Li+-H- ion pair in the melt. The absorption band ascribed to the vibration of K+-H- ion pair was not observed in the melt. The existence of the Li-H interaction shows a strong attractive force between H- ion and Li+ ion in the melt. (C) 2004 The Electrochemical Society.