A vacuum ultraviolet light emitting device comprising: a luminescence substrate which is composed of a transparent substrate of lithium fluoride, magnesium fluoride, calcium fluoride, barium fluoride or the like, and a metal fluoride thin-film layer formed on the transparent substrate and being a thin-film layer of a metal fluoride such as LuLiF4, LaF3, BaF2 or CaF2, the metal fluoride being doped with atoms of neodymium (Nd), thulium (Tm), erbium (Er) or the like; and an electron beam source such as a thermionic emission gun or a field emission gun, wherein the luminescence substrate and the electron beam source are disposed in a vacuum atmosphere, and the metal fluoride thin-film layer is irradiated with electron beams from the electron beam source to emit light including wavelength components of vacuum ultraviolet light.