| Kosei Hamaguchi | |
| Birth Date: | 11 April 1998 |
| Birth Place: | Fukutsu, Fukuoka, Japan |
| Height: | 1.83 m |
| Currentclub: | Kagoshima United |
| Clubnumber: | 37 |
| Position: | Defender |
| Youthclubs1: | Kamisaigo West Kids |
| Youthyears2: | –2016 |
| Youthclubs2: | Avispa Fukuoka |
| Youthyears3: | 2017–2020 |
| Youthclubs3: | N.I.F.S. |
| Years1: | 2020– |
| Caps1: | 0 |
| Goals1: | 0 |
| Club-Update: | 17:04, 9 June 2021 (UTC) |
is a Japanese footballer currently playing as a defender for Kagoshima United.
Hamaguchi made his professional debut in a 0–6 Emperor's Cup loss against Avispa Fukuoka.[1]
.
| Club | Season | League | National Cup | League Cup | Other | Total | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Division | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | |||
| N.I.F.S. | 2019 | – | 2 | 0 | – | 0 | 0 | 2 | 0 | ||||
| 2020 | 3 | 0 | – | 0 | 0 | 3 | 0 | ||||||
| Total | 0 | 0 | 5 | 0 | 0 | 0 | 0 | 0 | 5 | 0 | |||
| Kagoshima United | 2020 | J3 League | 0 | 0 | 0 | 0 | – | 0 | 0 | 0 | 0 | ||
| 2021 | 0 | 0 | 1 | 0 | – | 0 | 0 | 1 | 0 | ||||
| Total | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | |||
| Career total | 0 | 0 | 6 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | |||