| Event: | Men's singles SL4 |
| Games: | 2020 Summer |
| Venue: | Yoyogi National Gymnasium |
| Dates: | 2–5 September 2021 |
| Competitors: | 8 |
| Nations: | 6 |
| Gold: | Lucas Mazur |
| Goldnpc: | FRA |
| Silver: | Suhas Lalinakere Yathiraj |
| Silvernpc: | IND |
| Bronze: | Fredy Setiawan |
| Bronzenpc: | INA |
| Next: | 2024 |
The men's singles SL4 tournament at the 2020 Summer Paralympics in Tokyo took place between 2 and 5 September 2021 at Yoyogi National Gymnasium.[1]
These were the seeds for this event:[2]
The draw of the group stage revealed on 26 August 2021.[3] The group stage was played from 2 to 3 September. The top two winners of each group advanced to the knockout rounds.
| Date | Time | Player 1 | Score | Player 2 | Set 1 | Set 2 | Set 3 | |
|---|---|---|---|---|---|---|---|---|
| 2 Sep | 09:40 | Suhas Lalinakere Yathiraj  | 2–0 | Jan-Niklas Pott | 21–9 | 21–3 | ||
| 2 Sep | 09:40 | Lucas Mazur  | 2–0 | Hary Susanto | 21–3 | 21–7 | ||
| 3 Sep | 09:40 | Lucas Mazur | 2–0 | Jan-Niklas Pott | 21–3 | 21–7 | ||
| 3 Sep | 10:20 | Suhas Lalinakere Yathiraj | 2–0 | Hary Susanto | 21–6 | 21–12 | ||
| 3 Sep | 16:40 | Lucas Mazur | 2–0 | Suhas Lalinakere Yathiraj | 21–15 | 21–17 | ||
| 3 Sep | 16:40 | Jan-Niklas Pott | 2–0 | Hary Susanto | 21–15 | 23–21 |
| Date | Time | Player 1 | Score | Player 2 | Set 1 | Set 2 | Set 3 | |
|---|---|---|---|---|---|---|---|---|
| 2 Sep | 10:20 | Tarun Dhillon | 2–0 |  Siripong Teamarrom | 21–7 | 21–13 | ||
| 2 Sep | 10:20 | Fredy Setiawan | 2–0 |  Shin Kyung-hwan | 21–8 | 21–9 | ||
| 3 Sep | 09:40 | Fredy Setiawan | 2–0 | Siripong Teamarrom | 21–17 | 21–11 | ||
| 3 Sep | 10:20 | Tarun Dhillon | 2–1 | Shin Kyung-hwan | 21–18 | 15–21 | 21–17 | |
| 3 Sep | 17:20 | Tarun Dhillon | 0–2 | Fredy Setiawan | 19–21 | 9–21 | ||
| 3 Sep | 17:20 | Siripong Teamarrom | 0–2 | Shin Kyung-hwan | 17–21 | 8–21 |
The knockout stage was played from 4 to 5 September.