| Native Name: | 琴ヶ濵 貞雄 |
| Kotogahama Sadao | |
| Birth Name: | Usō Sadao |
| Birth Date: | 1927 10, df=yes |
| Birth Place: | Kanonji, Kagawa, Japan |
| Weight: | 117kg (258lb) |
| Heya: | Nishonoseki → Sadogatake |
| Record: | 441-352-92 |
| Debut: | November 1945 |
| Highestrank: | Ōzeki (May 1958) |
| Retireddate: | November 1962 |
| Eldername: | Oguruma |
| Prizes: | Outstanding Performance (2) Technique (5) Fighting Spirit (1) |
| Goldstars: | 7 Tochinishiki (3) Chiyonoyama (2) Kagamisato Yoshibayama |
| Update: | June 2020 |
Kotogahama Sadao (Jap 琴ヶ濵貞雄) (10 October 1927 – 7 June 1981) was a sumo wrestler from Kanonji, Kagawa, Japan.
He reached the second highest rank of ōzeki in 1958. He was a tournament runner-up in the top makuuchi division on five occasions and earned seven kinboshi for defeating yokozuna when ranked as a maegashira. After his retirement in 1962 he became an elder in the Japan Sumo Association and worked as a coach at Sadogatake stable. He was offered the chance to take charge of the stable in 1974 but declined, preferring to remain as an assistant coach there until his death in 1981.