A white light-emitting device using a fluorescent fiber includes a blue semiconductor light-emitting element (2) for emitting an excitation light (a), and an optical fiber (3) having one side end face and the other side end face, the excitation light (a) emitted from the blue semiconductor light-emitting element (2) being made incident to the one side end face to be guided to the other side end face. The optical fiber (3) includes a core containing therein a phosphor for emitting wavelength conversion lights by being excited by the excitation light (a) received from the blue semiconductor light-emitting element (2), and a cladding member (3B) having a light emission surface in its peripheral surface, at least a part of optically multiplexed lights, which are obtained by optically multiplexing the wavelength conversion lights and the excitation light, being emitted through the light emission surface.