2021 Open Sopra Steria de Lyon – Singles

Corentin Moutet was the defending champion but chose not to defend his title.

Pablo Cuevas won the title after defeating Elias Ymer 6–2, 6–2 in the final.

Seeds
• # Pablo Cuevas (champion)

• # 🇪🇸 Fernando Verdasco (second round)

• # 🇦🇷 Facundo Bagnis (semifinals)

• # 🇨🇴 Daniel Elahi Galán (second round)

• # 🇯🇵 Taro Daniel (semifinals)

• # 🇫🇷 Benjamin Bonzi (first round)

• # 🇦🇷 Francisco Cerúndolo (first round)

• # 🇩🇪 Cedrik-Marcel Stebe (quarterfinals)