| Native Name: | 佐田の海 鴻嗣 |
| Sadanoumi Kōji | |
| Birth Name: | Hiroshi Matsumara |
| Birth Date: | 1956 7, df=yes |
| Birth Place: | Sakai, Osaka, Japan |
| Weight: | 126kg (278lb) |
| Heya: | Dewanoumi |
| Record: | 544-581-7 |
| Debut: | March, 1972 |
| Highestrank: | Komusubi (January, 1982) |
| Retireddate: | July, 1988 |
| Eldername: | Tagonoura |
| Yushos: | 1 (Makushita) 1 (Jonokuchi) |
| Prizes: | Outstanding Performance (1) Fighting Spirit (2) Technique (1) |
| Update: | June 25, 2020 |
(born 19 July 1956 as) is a former sumo wrestler from Sakai, Osaka, Japan. He made his professional debut in March 1972, and reached the top division in November 1980. His highest rank was komusubi. He retired in July 1988 and became an elder in the Japan Sumo Association under the name Tagonoura. He left the Sumo Association in August 1999.[1] He is the father of the current sekitori wrestler of the same name, Sadanoumi Takashi.