Target for X-ray generator, method of manufacturing the same and X-ray generator

There is provided a target for an X-ray generator, including: a holder part made of an electrically conductive material and having an opening part; a diamond plate air-tightly joined to the holder part so as to close the opening part; a thin film target provided on a surface of the diamond plate, with its outer peripheral part extending to the holder part to be electrically connected to the holder part, wherein the holder part is configured to be electrically connected to a power supply of the X-ray generator, and the diamond plate is incorporated into the X-ray generator with one side disposed in a vacuum atmosphere where the thin film target is formed, and an opposite side thereto disposed at a side where the diamond plate is brought into thermal contact with a refrigerant and cooled.