| 2021 Bucharest Challenger | |
|---|---|
| Date | 20–26 September |
| Edition | 1st |
| Surface | Clay |
| Location | Bucharest, Romania |
| Champions | |
| Singles | |
 Jiří Lehečka | |
| Doubles | |
 Ruben Gonzales /  Hunter Johnson | |
The 2021 Bucharest Challenger was a professional tennis tournament played on clay courts. It was the 1st edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Bucharest, Romania between 20 and 26 September 2021.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 ITA | Stefano Travaglia | 99 | 1 |
 MDA | Radu Albot | 105 | 2 |
 AUS | Thanasi Kokkinakis | 180 | 3 |
| CZE | Zdeněk Kolář | 185 | 4 |
 IND | Sumit Nagal | 186 | 5 |
 GER | Maximilian Marterer | 197 | 6 |
| CZE | Vít Kopřiva | 198 | 7 |
| CZE | Jiří Lehečka | 201 | 8 |
The following players received wildcards into the singles main draw:
Nicolae Frunză David Ionel Ștefan PaloșiThe following players received entry into the singles main draw as alternates:
The following players received entry from the qualifying draw:
Jiří Lehečka def. 
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