A UV sterilization tube includes a hollow tube, a hydroelectric power module and a UV sterilization module. The hollow tube includes an inlet end and an outlet end communicating with each other. The hydroelectric power module is positioned in the hollow tube, and communicates with the inlet end and the outlet end of the hollow tube, wherein the hydroelectric power module generates electric power by a water flow. The UV sterilization module is positioned in the hollow tube, and is electrically connected to the hydroelectric power module. The UV sterilization module includes a UV source and a reflector, wherein the UV source has a light-emitting surface facing to the reflector. A sterilization channel, which communicates with the inlet end and the outlet end of the hollow tube, is between the UV source and the reflector.