| Champ: |  Hubert Hurkacz |
| Runner: |  Pablo Carreño Busta |
| Score: | 7–6(7–2), 6–3 |
| Draw: | 28 (4 / 3) |
| Seeds: | 8 |
| Before Year: | 2019 |
| Type: | singles doubles |
See main article: article and 2021 Moselle Open.
Jo-Wilfried Tsonga was the reigning champion from when the tournament was last held in 2019,[1] but chose not to participate this year.
Hubert Hurkacz won the title, defeating Pablo Carreño Busta in the final, 7–6(7–2), 6–3.
The top four seeds received a bye into the second round.