2021 Saint Petersburg Challenger – Singles

This was the first edition of the tournament.

Zizou Bergs won the title after defeating Altuğ Çelikbilek 6–4, 3–6, 6–4 in the final.

Seeds
• # 🇷🇺 Roman Safiullin (first round)

• # 🇹🇷 Cem İlkel (quarterfinals)

• # 🇩🇪 Rudolf Molleker (first round)

• # 🇺🇸 Christopher Eubanks (first round)

• # 🇷🇺 Teymuraz Gabashvili (first round)

• # 🇷🇺 Alexey Vatutin (second round)

• # 🇪🇨 Roberto Quiroz (second round)

• # 🇷🇺 Evgeny Karlovskiy (first round)