An x-ray marker for an endoprosthesis and an endoprosthesis with an x-ray marker are provided. The endoprosthesis includes a hollow cylinder made of a first radiopaque metal and a marker element, which is fixedly connected to the hollow cylinder and which is arranged inside the hollow cylinder and consists of a second radiopaque metal. The marker element can be a metal powder or in the form of metal particles which is/are embedded in the electrically non-conductive material. The marker element can be solid cylinder with a diameter smaller than the inner diameter of the hollow cylinder and the electrically non-conductive material can form a layer between an inner lateral surface of the hollow cylinder and a lateral surface of the solid cylinder