Barium sulfide is the inorganic compound with the formula BaS. BaS is the barium compound produced on the largest scale. It is an important precursor to other barium compounds including BaCO₃ and the pigment lithopone, ZnS/BaSO₄. Like other chalcogenides of the alkaline earth metals,

BaS is a short wavelength emitter for electronic displays. It is colorless, although like many sulfides, it is commonly obtained in impure colored forms.