| Native Name: | 清の盛 政夫 |
| Kiyonomori Masao | |
| Birth Name: | Masao Sasaki |
| Birth Date: | 8 April 1935 |
| Birth Place: | Ōmori, Akita, Japan |
| Weight: | 92kg (203lb) |
| Heya: | Isegahama |
| Record: | 519-504-7-1 (draw) |
| Debut: | January, 1953 |
| Highestrank: | Maegashira 9 (May, 1960) |
| Retireddate: | May, 1967 |
| Eldername: | Kise |
| Yushos: | 2 (Jūryō) |
| Update: | June 2020 |
Kiyonomori Masao (8 April 1935 – 20 April 2019, real name Masao Sasaki) was a sumo wrestler from Ōmori, Akita, Japan. He made his professional debut in January 1953 and reached the top division in March 1959. His highest rank was maegashira 9. Upon retirement from active competition he became an elder in the Japan Sumo Association and took charge of Kise stable from his father-in-law Katsuragawa. He reached the Sumo Association's mandatory retirement age in April 2000.[1] [2] He died of pneumonia in April 2019 at the age of 84.[3]