The Tokyo 3rd district (東京都第3区, Tōkyō-to dai-san-ku) is a constituency of the House of Representatives in the Diet of Japan (national legislature). It is located in Tokyo and covers parts of the former city of Tokyo and Tokyo's outlying islands. The district consists of the wards of Shinagawa and parts of Ōta, the towns of Ōshima and Hachijō and the villages of Toshima, Niijima, Kōzushima, Miyake, Mikurajima, Aogashima and Ogasawara. As of 2012, 482,494 eligible voters were registered in the district.