| 2021 Brest Challenger | |
|---|---|
| Date | 25–31 October |
| Edition | 6th |
| Surface | Hard, Indoor |
| Location | Brest, France |
| Champions | |
| Singles | |
 Brandon Nakashima | |
| Doubles | |
 Sadio Doumbia / Fabien Reboul | |
The 2021 Brest Challenger was a professional tennis tournament played on hard courts. It was the sixth edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Brest, France between 25 and 31 October 2021.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
| FRA | Arthur Rinderknech | 65 | 1 |
| USA | |||
| FRA | Richard Gasquet | 74 | 3 |
| USA | Brandon Nakashima | 79 | 4 |
 ITA | Stefano Travaglia | 83 | 5 |
| FRA | Pierre-Hugues Herbert | 97 | 6 |
 SUI | Henri Laaksonen | 99 | 7 |
| FRA | Hugo Gaston | 106 | 8 |
The following players received wildcards into the singles main draw:
The following player received entry into the singles main draw as a special exempt:
The following player received entry into the singles main draw as an alternate:
The following players received entry from the qualifying draw:
The following player received entry as a lucky loser:
Valentin Royer Brandon Nakashima def. 
João Sousa 6–3, 6–3. Sadio Doumbia / Fabien Reboul def. Salvatore Caruso / Federico Gaio 4–6, 6–3, [10–3].The 2015 Brest Challenger was a professional tennis tournament played on hard courts. It was the first edition of the tournament which was part of the 2015 ATP Challenger Tour. It took place at the Brest Arena in Brest, France between 19 and 25 October 2015.
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