[Object] The present invention relates to a sterilizer an oral sterilizer a sterilization method a sterilization apparatus and a sterilizer evaluation method capable of increasing a sterilization effect. [Solution] The sterilizer which contains hydrogen peroxide and a catalase activity inhibitor formed of scutellaria or green tea is brought into contact with a sterilization target such as a tooth and a denture in an oral cavity. Then by using a light emitter formed of a semiconductor laser light is irradiated onto the sterilization target at a wavelength of between 350 nm and 500 nm. As a result the hydrogen peroxide is photolyzed to generate hydroxyl radicals and sterilization may be performed by the hydroxyl radicals.
