| Marina Saito | |
| Birth Date: | 15 October 1995 |
| Birth Place: | Ibaraki Prefecture, Japan[1] |
| Height: | 1.64 m |
| Weight: | 65 kg |
| Sport: | Athletics |
| Event: | Javelin throw |
| Education: | Kokushikan University[2] |
is a Japanese athlete specialising in the javelin throw. She represented her country at the 2017 World Championships. In addition, she won the silver medal at the 2017 Summer Universiade.
Her personal best in the event is 62.37 metres set in Taipei in 2017.[3]
| 2017 | World Championships | London, United Kingdom | 16th (q) | 60.86 m | |
| Universiade | Taipei, Taiwan | bgcolor=silver | 2nd | 62.37 m | |
| 2018 | Asian Games | Jakarta, Indonesia | 4th | 56.46 m | |
| 2019 | Asian Championships | Doha, Qatar | 9th | 52.40 m | |
| 2023 | Asian Championships | Bangkok, Thailand | bgcolor=gold | 1st | 61.67 m |
| World Championships | Budapest, Hungary | 15th (q) | 58.95 m | ||
| Asian Games | Hangzhou, China | 4th | 61.10 m | ||
| 2024 | Olympic Games | Paris, France | 21st (q) | 59.42 m |