| 2021 Saint Petersburg Challenger | |
|---|---|
| Date | 1–7 March |
| Edition | 1st |
| Surface | Hard (Indoor) |
| Location | Saint Petersburg, Russia |
| Champions | |
| Singles | |
 Zizou Bergs | |
| Doubles | |
 Christopher Eubanks /  Roberto Quiroz | |
The 2021 Saint Petersburg Challenger was a professional tennis tournament played on hard courts. It was the first edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Saint Petersburg, Russia between 1 and 7 March 2021.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 RUS | Roman Safiullin | 164 | 1 |
 TUR | Cem İlkel | 208 | 2 |
 GER | Rudolf Molleker | 223 | 3 |
| USA | Christopher Eubanks | 240 | 4 |
| RUS | Teymuraz Gabashvili | 247 | 5 |
| RUS | Alexey Vatutin | 258 | 6 |
| ECU | Roberto Quiroz | 262 | 7 |
| RUS | Evgeny Karlovskiy | 267 | 8 |
The following players received wildcards into the singles main draw:
The following players received entry from the qualifying draw:
Zizou Bergs def. Altuğ Çelikbilek 6–4, 3–6, 6–4. Christopher Eubanks / Roberto Quiroz def. 
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