2021 Mallorca Championships – Singles

Daniil Medvedev defeated Sam Querrey in the final, 6–4, 6–2, to win the singles tennis title at the 2021 Mallorca Championships. It was Medvedev's first career grass court final and singles title on the ATP Tour, and he dropped just one set en route to the victory. Querrey was contesting for his first title in four years.

This was the inaugural edition of the tournament.

Seeds
The top four seeds received a bye into the second round. • # 🇷🇺 Daniil Medvedev (champion)

• # 🇦🇹 Dominic Thiem (second round, retired due to wrist injury)

• # 🇪🇸 Roberto Bautista Agut (quarterfinals)

• # 🇪🇸 Pablo Carreño Busta (semifinals)

• # 🇳🇴 Casper Ruud (quarterfinals)

• # 🇷🇺 Karen Khachanov (second round)

• # 🇫🇷 Ugo Humbert (second round, withdrew due to food poisoning)

• # 🇷🇸 Dušan Lajović (first round)

Seeds
• # Pablo Cuevas (first round)

• # 🇲🇩 Radu Albot (qualifying competition)

• # 🇫🇷 Lucas Pouille (qualified)

• # 🇪🇸 Roberto Carballés Baena (qualified)

• # 🇪🇸 Pedro Martínez (first round)

• # João Sousa (qualifying competition)

• # 🇨🇴 Daniel Elahi Galán (first round)

• # 🇺🇿 Denis Istomin (qualifying competition)

Qualifiers
• # 🇸🇰 Lukáš Klein

• # 🇪🇸 Nicola Kuhn

• # 🇫🇷 Lucas Pouille

• # 🇪🇸 Roberto Carballés Baena