2021 Wimbledon Championships – Boys' singles

Shintaro Mochizuki was the defending champion having won the previous edition in 2019. He participated in the men's singles qualifying, but lost to Tallon Griekspoor in the second round.

Samir Banerjee won the title, defeating Victor Lilov in the final, 7–5, 6–3.

Seeds
• 🇨🇳 Shang Juncheng (semifinals)

• 🇫🇷 Luca Van Assche (first round)

• 🇫🇷 Arthur Fils (second round)

• 🇺🇸 Bruno Kuzuhara (quarterfinals)

• 🇧🇷 Pedro Boscardin Dias (third round)

• 🇪🇸 Daniel Rincón (second round)

• 🇬🇧 Jack Pinnington Jones (quarterfinals)

• 🇫🇷 Sean Cuenin (second round)

• 🇺🇦 Viacheslav Bielinskyi (second round)

• 🇺🇸 Dali Blanch (first round)

• Jérôme Kym (quarterfinals)

• 🇵🇱 Maks Kaśnikowski (first round)

• 🇺🇸 Alexander Bernard (second round)

• 🇸🇪 Leo Borg (second round)

• 🇪🇸 Alejandro Manzanera Pertusa (second round)

• 🇪🇪 Mark Lajal (second round)

Seeds
• # 🇫🇷 Sascha Gueymard Wayenburg (qualified)

• # 🇧🇪 Martin Katz (first round)

• # 🇱🇹 Vilius Gaubas (first round)

• # Mili Poljičak (qualified)

• # 🇩🇪 Philip Florig (first round)

• # 🇦🇹 Marko Andrejic (first round)

• # 🇷🇺 Igor Kudriashov (qualified)

• # 🇺🇸 Aidan Kim (first round)

• # Sebastian Dominko (first round)

• # 🇫🇷 Robin Bertrand (qualified)

• # 🇺🇸 Azuma Visaya (first round)

• # 🇺🇸 Braden Shick (qualifying competition)

• # 🇦🇷 Ezequiel Monferrer (qualifying competition)

• # 🇮🇱 Orel Kimhi (qualified)

• # Luka Mikrut (first round)

• # 🇪🇸 Miguel Pérez Peña (first round)

Qualifiers
• # 🇫🇷 Sascha Gueymard Wayenburg

• # 🇬🇧 Patrick Brady

• # 🇬🇧 Billy Blaydes

• # Mili Poljičak

• # 🇫🇷 Charlélie Cosnet

• # 🇫🇷 Robin Bertrand

• # 🇷🇺 Igor Kudriashov

• # 🇮🇱 Orel Kimhi