Akashi Shiganosuke (Japanese: 明石 志賀之助, c. 1600 – c. 1649) is purported to be a Japanese sumo wrestler in antiquity who is formally recognized as the first yokozuna. A legendary figure, his historical existence is disputed. He is said to have been active in the Kan'ei era (1624–1643). He was described as being of gigantic size, at 2.58 m (8 ft 6 in) tall and weighing 340 kg (750 lb). He is said to have been born in Utsunomiya, Tochigi prefecture in central Japan, the son of , a samurai who served .