| Seiya Niizeki | |
| Fullname: | Seiya Niizeki |
| Birth Date: | 28 April 1999 |
| Birth Place: | Shizuoka, Japan |
| Position: | Midfielder |
| Currentclub: | Shimizu S-Pulse |
| Clubnumber: | 47 |
| Youthyears1: | 2015–2017 |
| Youthclubs1: | Shimizu S-Pulse |
| Years1: | 2017– |
| Clubs1: | Shimizu S-Pulse |
is a Japanese football player. He plays for Shimizu S-Pulse.
Seiya Niizeki joined J1 League club Shimizu S-Pulse in 2017.