2023 US Open – Boys' singles

João Fonseca won the boys' singles title at the 2023 US Open, defeating Learner Tien in the final, 4–6, 6–4, 6–3.

Martín Landaluce was the reigning champion, but chose not to participate.

Seeds
• Yaroslav Demin (third round)

• 🇲🇽 Rodrigo Pacheco Méndez (quarterfinals)

• 🇺🇸 Cooper Williams (quarterfinals)

• 🇬🇧 Henry Searle (second round)

• 🇧🇴 Juan Carlos Prado Ángelo (second round)

• 🇧🇬 Iliyan Radulov (first round)

• 🇧🇷 João Fonseca (champion)

• 🇺🇸 Darwin Blanch (third round)

• 🇨🇳 Zhou Yi (quarterfinals)

• 🇷🇸 Branko Đurić (first round)

• 🇺🇸 Learner Tien (final)

• 🇵🇱 Tomasz Berkieta (first round)

• 🇦🇹 Joel Schwärzler (first round)

• 🇮🇹 Federico Cinà (semifinals)

• 🇫🇷 Arthur Géa (semifinals)

• 🇪🇸 Alejandro Melero Kretzer (first round)

Seeds
• # 🇪🇸 Rafael Jodar (qualified)

• # 🇦🇺 Pavle Marinkov (qualified)

• # 🇨🇳 Zhang Tianhui (qualified)

• # 🇮🇳 Aryan Shah (qualified)

• # 🇺🇦 Volodymyr Iakubenko (qualifying competition)

• # 🇬🇧 Charlie Robertson (first round)

• # 🇮🇹 Fabio De Michele (qualified)

• # 🇰🇷 Roh Ho-young (qualified)

• # 🇸🇪 Albert Saar (qualifying competition)

• # 🇧🇷 Gustavo Ribeiro de Almeida (first round)

• # 🇹🇷 Atakan Karahan (qualified)

• # 🇮🇳 Manas Dhamne (first round)

• # 🇻🇪 Ignacio Parisca (qualifying competition)

• # 🇪🇪 Markus Mölder (qualifying competition, lucky loser)

• # 🇲🇦 Ilyas Milad Fahim (first round)

• # 🇬🇧 Luca Pow (qualifying competition)

Qualifiers
• # 🇪🇸 Rafael Jodar

• # 🇦🇺 Pavle Marinkov

• # 🇨🇳 Zhang Tianhui

• # 🇮🇳 Aryan Shah

• # 🇹🇷 Atakan Karahan

• # 🇰🇷 Park Seung-min

• # 🇮🇹 Fabio De Michele

• # 🇰🇷 Roh Ho-young

Lucky loser

 * 1) 🇪🇪 Markus Mölder