An ultraviolet laser device comprises a laser beam output unit that outputs infra-red laser beams, and a wavelength conversion unit that wavelength converts the infra-red laser beams. The laser beam output unit comprises a first laser beam output unit that outputs a first infra-red laser beam whose wavelength is 1900-2000 nm, and a second laser beam output unit that outputs a second infra-red laser beam whose wavelength is 1000-1100 nm. The wavelength conversion unit comprises a first element series that the first infra-red light beam is incident upon and propagated through, and a second element series that the laser light propagated through the first element series and the second infra-red laser beam are incident upon, combined in, and propagated through, and constructed so that ultraviolet laser light is outputted, due to the first and second infra-red laser beams being wavelength converted by optical wavelength conversion elements.