The present invention has as its object the provision of an ultraviolet sterilizer that can reduce ultraviolet light in a wavelength region of 230 to 300 nm, which is harmful to the human body, and can output effective light in a wavelength region of 200 to 230 nm with high emission intensity.The ultraviolet sterilizer of the present invention is an ultraviolet sterilizer comprising: an ultraviolet light source； a lamp storage chamber for storing the ultraviolet light source； and alight guiding part for guiding light from the ultraviolet light source, in which a band pass filter for reducing ultraviolet light in a wavelength region harmful to a human body is provided at least one of a position between the light guiding part and the lamp storage chamber and a position of a light outputting leading end of the light guiding part, and an inner surface of the light guiding part is formed from an ultraviolet absorbing member that absorbs the ultraviolet light in the wavelength region harmful to the human body.
