Map of Tokyo Bay, 1917

Tokyo Bay (東京湾; Tōkyō-wan) is a bay in the southern Kanto region of Japan, surrounded by the Boso Peninsula (Chiba Prefecture) and the Miura Peninsula (Kanagawa Prefecture). The ports of Tokyo, Chiba, Kawasaki, Yokohama, and Yokosuka are all located on Tokyo Bay.

On the west coast of Tokyo Bay, between Tokyo and Yokohama, the Keihin Industrial Area has been developed since the Meiji Era. This was expanded to Keiyo Industrial Area along the north and east coasts after World War II.

The Tokyo Bay Aqualine bridge/tunnel crosses Tokyo Bay between Kawasaki and Nakajima: ferries also cross the bay toward the Uraga Channel end.

Tokyo Bay was the venue for Commodore Matthew Perry's early negotiations with the Japanese bakufu in the 1850's, as well as most official Japanese-European contacts preceding the Meiji Restoration.