PROBLEM TO BE SOLVED: To provide a sterilizer for a container, irradiating ultraviolet rays evenly to a lateral face in addition to a bottom of the container, in a state of being inserted into the inside of the container while including a small-sized ultraviolet irradiation part.SOLUTION: A sterilizer 1 includes single or a plurality of LED light sources 4 receiving an electrical power and emitting ultraviolet rays UV, and a light source support body supporting the LED light source 4 and capable of advancing-retreating to a preform 30 as a sterilization object. The sterilizer 1 includes preferably a light diffusion cover 10 covering at least the LED light source 4, and irradiates ultraviolet rays UV from the LED light source 4 preferably in both of an outward route to the inside of the preform 30 and a homeward route from the preform 30 to the outside.SELECTED DRAWING: Figure 1
