The invention belongs to the technical field of fusion reactor penetration piece, and more specifically relates to a double-layer electrically-charged waterway penetration piece used on a fusion reactor vacuum side. According to the double-layer electrically-charged waterway penetration piece, a first layer electrical isolation constraint structure is arranged in a second layer electrical isolation constraint structure concentrically to form an electrical isolation constraint structure; an insulation cavity is composed of the first layer electrical isolation constraint structure and the secondlayer electrical isolation constraint structure; the left end of the first layer electrical isolation constraint structure and the left end of the second layer electrical isolation constraint structure are arranged on a separating plate; an ITER flange is of a circular disc structure; the center of the ITER flange is provided with a through hole; the left end of the first layer electrical isolation constraint structure and the left end of the second layer electrical isolation constraint structure are welded on the right side surface of the ITER flange; the ITER flange is provided with a plurality of bolt holes; the ITER flange is arranged on a constrain barrier CP flange vacuum side through ITER flange fastening bolts; the center of the separating plate is provided with a through hole; anelectrically charge water pipe is designed to pass through the CP flange center hole, the ITER flange center through hole, the first layer electrical isolation constraint structure, and the separating plate center through hole, and stretch into the vacuum side.