2021 Aberto da República – Men's singles

This was the first edition of the tournament.

Federico Coria won the title after defeating Jaume Munar 7–5, 6–3 in the final.

Seeds
• # 🇦🇷 Federico Coria (champion)

• # 🇪🇸 Jaume Munar (final)

• # 🇦🇷 Sebastián Báez (withdrew)

• # 🇦🇷 Francisco Cerúndolo (semifinals, retired)

• # 🇧🇴 Hugo Dellien (second round)

• # 🇦🇷 Tomás Martín Etcheverry (first round)

• # 🇧🇷 Thiago Seyboth Wild (quarterfinals)

• # 🇦🇷 Juan Ignacio Londero (quarterfinals)