2021 US Open – Men's singles qualifying

The 2021 US Open – Men's Singles Qualifying was a series of tennis matches from 24 August 2021 to 27 August 2021 where 128 players compete to determine the 16 qualifiers into the main draw of the 2021 US Open men's singles tournament, and, if necessary, the lucky losers. Due to pandemic-related restrictions, the qualifying matches were not open to the public.

Seeds
• #🇫🇷 Benjamin Bonzi (second round)

• #🇦🇷 Francisco Cerúndolo (qualifying competition)

• #🇨🇴 Daniel Elahi Galán (first round)

• #🇵🇱 Kamil Majchrzak (qualified)

• #🇪🇸 Bernabé Zapata Miralles (qualifying competition, lucky loser)

• # Botic van de Zandschulp (qualified)

• #🇧🇦 Damir Džumhur (second round)

• #🇯🇵 Yasutaka Uchiyama (first round)

• #🇵🇪 Juan Pablo Varillas (first round)

• #🇦🇺 Christopher O'Connell (second round)

• #🇫🇷 Hugo Gaston (second round)

• # Pedro Sousa (first round)

• #🇰🇿 Mikhail Kukushkin (qualifying competition, lucky loser)

• # Henri Laaksonen (qualified)

• #🇯🇵 Yūichi Sugita (qualifying competition, lucky loser)

• #🇪🇸 Fernando Verdasco (second round)

• #🇧🇴 Hugo Dellien (second round)

• #🇸🇰 Alex Molčan (qualified)

• #🇦🇹 Jurij Rodionov (qualifying competition)

• #🇩🇪 Peter Gojowczyk (qualified)

• #🇦🇷 Tomás Martín Etcheverry (first round)

• #🇨🇿 Tomáš Macháč (first round)

• #🇩🇪 Oscar Otte (qualified)

• # Holger Rune (qualified)

• #🇬🇧 Liam Broady (second round)

• #🇦🇺 Marc Polmans (first round)

• # João Sousa (first round)

• #🇫🇷 Antoine Hoang (qualified)

• #🇺🇸 Maxime Cressy (qualified)

• #🇷🇺 Evgeny Donskoy (qualified)

• #🇦🇷 Juan Ignacio Londero (first round)

• #🇺🇦 Illya Marchenko (second round)

Qualifiers
• #🇦🇷 Marco Trungelliti

• #🇩🇪 Peter Gojowczyk

• #🇺🇸 Christopher Eubanks

• #🇵🇱 Kamil Majchrzak

• #🇩🇪 Oscar Otte

• # Botic van de Zandschulp

• #🇷🇺 Evgeny Donskoy

• #🇫🇷 Quentin Halys

• #🇩🇪 Maximilian Marterer

• # Holger Rune

• #🇺🇸 Maxime Cressy

• #🇸🇰 Alex Molčan

• #🇫🇷 Antoine Hoang

• # Henri Laaksonen

• # Ivo Karlović

• #🇹🇷 Cem İlkel

Lucky losers
• #🇪🇸 Bernabé Zapata Miralles

• #🇰🇿 Mikhail Kukushkin

• #🇯🇵 Yūichi Sugita