2021 Dubai Tennis Championships – Men's singles

Aslan Karatsev won his first ATP Tour singles title, defeating Lloyd Harris in the final, 6–3, 6–2 to win the men's singles tennis title at the 2021 Dubai Tennis Championships. Karatsev became the second wildcard in the tournament's history to win the men's singles title. Harris was the first qualifier to reach the final of the Dubai Tennis Championships.

Novak Djokovic was the defending champion, but chose not to participate.

Seeds
All seeds receive a bye into the second round. • #🇦🇹 Dominic Thiem (second round)

• #🇷🇺 Andrey Rublev (semifinals)

• #🇨🇦 Denis Shapovalov (semifinals)

• #🇪🇸 Roberto Bautista Agut (third round)

• #🇧🇪 David Goffin (second round)

• #🇪🇸 Pablo Carreño Busta (second round)

• # Stan Wawrinka (withdrew)

• #🇷🇺 Karen Khachanov (third round)

• #🇦🇺 Alex de Minaur (second round)

• # Borna Ćorić (withdrew)

• #🇷🇸 Dušan Lajović (third round)

• #🇬🇧 Dan Evans (second round)

• #🇵🇱 Hubert Hurkacz (third round)

• #🇷🇸 Filip Krajinović (third round)

• #🇺🇸 Taylor Fritz (third round)

• #🇮🇹 Jannik Sinner (quarterfinals)

• #🇮🇹 Lorenzo Sonego (third round)

The players who also received a bye into the second round were as follows, each semifinalist from Doha or Marseille:
 * Nikoloz Basilashvili
 * 🇦🇺 Matthew Ebden

The other six byes were removed, and six players were added to the main draw.

Seeds
• # 🇲🇩 Radu Albot (qualifying competition, lucky loser)

• # Lloyd Harris (qualified)

• # 🇫🇮 Emil Ruusuvuori (qualified)

• # 🇰🇿 Mikhail Kukushkin (qualified)

• # 🇦🇺 Christopher O'Connell (qualified)

• # 🇷🇺 Evgeny Donskoy (first round)

• # 🇮🇳 Prajnesh Gunneswaran (first round)

• # 🇦🇺 Marc Polmans (first round)

• # 🇪🇸 Bernabé Zapata Miralles (qualified)

• # 🇮🇹 Lorenzo Giustino (qualifying competition, lucky loser)

• # Blaž Rola (qualifying competition)

• # 🇮🇹 Thomas Fabbiano (qualifying competition)

Qualifiers
• # 🇪🇸 Bernabé Zapata Miralles

• # Lloyd Harris

• # 🇫🇮 Emil Ruusuvuori

• # 🇰🇿 Mikhail Kukushkin

• # 🇦🇺 Christopher O'Connell

• # 🇮🇳 Yuki Bhambri

Lucky losers
• # 🇲🇩 Radu Albot

• # 🇮🇹 Lorenzo Giustino