Abstract: An ultraviolet-irradiating device of an optical disk which makes effective use of electric power and has a long life, and an ultraviolet-irradiating method to an optical disk are provided. An ultraviolet-irradiating device 14 of an optical disk for irradiating ultraviolet curable resin A applied to a disk substrate D with ultraviolet rays from an ultraviolet-irradiating unit 143 to cure the ultraviolet curable resin A, wherein an ultraviolet light-emitting diode R is used as an ultraviolet light source of the ultraviolet-irradiating unit 143. According to the present invention, since the ultraviolet light-emitting diode R is used as an ultraviolet light source, lights in a visible region and an infrared region are not emitted like a conventional xenon lamp, that is, only ultraviolet rays required for curing the ultraviolet curable resin can be irradiated, so that power consumption required for light emission of the light source can be reduced.