2019 Miami Open – Men's singles

Roger Federer defeated the defending champion John Isner in the final, 6–1, 6–4 to win the men's singles tennis title at the 2019 Miami Open. It was Federer's fourth Miami Open title, his 28th and final Masters singles title, and his 101st career singles title overall.

Félix Auger-Aliassime became the youngest men's singles semifinalist in the tournament's 35-year history, and the first teenage semifinalist since Andy Murray and Novak Djokovic in 2007.

Seeds
All seeds received a bye into the second round. • 🇷🇸 Novak Djokovic (fourth round)

• 🇩🇪 Alexander Zverev (second round)

• 🇦🇹 Dominic Thiem (second round)

• Roger Federer (champion)

• 🇯🇵 Kei Nishikori (second round)

•  Kevin Anderson (quarterfinals)

• 🇺🇸 John Isner (final)

•  Stefanos Tsitsipas (fourth round)

•  Marin Čilić (second round)

• 🇷🇺 Karen Khachanov (second round)

•  Borna Ćorić (quarterfinals)

• 🇨🇦 Milos Raonic (third round)

• 🇷🇺 Daniil Medvedev (fourth round)

• 🇮🇹 Marco Cecchinato (third round)

• 🇮🇹 Fabio Fognini (third round)

• 🇫🇷 Gaël Monfils (withdrew)

•  Nikoloz Basilashvili (fourth round)

• 🇧🇪 David Goffin (fourth round)

• 🇬🇧 Kyle Edmund (fourth round)

• 🇨🇦 Denis Shapovalov (semifinals)

• 🇦🇷 Diego Schwartzman (second round)

• 🇪🇸 Roberto Bautista Agut (quarterfinals)

• 🇫🇷 Gilles Simon (second round)

• 🇧🇬 Grigor Dimitrov (third round)

• 🇫🇷 Lucas Pouille (second round)

• 🇦🇷 Guido Pella (second round)

• 🇦🇺 Nick Kyrgios (fourth round)

• 🇺🇸 Frances Tiafoe (quarterfinals)

• 🇭🇺 Márton Fucsovics (second round)

•  Stan Wawrinka (second round)

• 🇺🇸 Steve Johnson (second round)

• 🇦🇺 John Millman (second round)

Seeds
• # 🇲🇩 Radu Albot (qualified)

• # 🇨🇦 Félix Auger-Aliassime (qualified)

• # 🇺🇸 Reilly Opelka (qualified)

• # 🇺🇸 Mackenzie McDonald (qualifying competition, lucky loser)

• # 🇦🇷 Juan Ignacio Londero (first round)

• # Cristian Garín (first round)

• # Pablo Cuevas (qualified)

• # 🇧🇴 Hugo Dellien (first round)

• # Lloyd Harris (qualifying competition. Lucky loser)

• # 🇳🇴 Casper Ruud (qualified)

• # 🇱🇹 Ričardas Berankis (first round)

• # 🇮🇳 Prajnesh Gunneswaran (qualified)

• # 🇬🇧 Dan Evans (qualifying competition, lucky loser)

• # 🇺🇿 Denis Istomin (qualifying competition, withdrew)

• # 🇷🇺 Andrey Rublev (qualified)

• # 🇺🇸 Ryan Harrison (first round)

• # 🇮🇹 Paolo Lorenzi (qualifying competition)

• # 🇮🇹 Lorenzo Sonego (qualified)

• # 🇪🇸 Marcel Granollers (qualifying competition)

• # 🇸🇰 Jozef Kovalík (first round)

• # 🇸🇪 Elias Ymer (first round)

• # 🇫🇷 Jo-Wilfried Tsonga (qualifying competition)

• # 🇧🇷 Thiago Monteiro (qualified)

• # 🇷🇺 Evgeny Donskoy (qualifying competition)

Qualifiers
• # 🇲🇩 Radu Albot

• # 🇨🇦 Félix Auger-Aliassime

• # 🇺🇸 Reilly Opelka

• # 🇮🇹 Lorenzo Sonego

• # 🇸🇰 Lukáš Lacko

• # 🇷🇺 Andrey Rublev

• # Pablo Cuevas

• # 🇸🇪 Mikael Ymer

• # 🇧🇷 Thiago Monteiro

• # 🇳🇴 Casper Ruud

• # 🇰🇿 Alexander Bublik

• # 🇮🇳 Prajnesh Gunneswaran

Lucky losers
• # 🇺🇸 Mackenzie McDonald

• # 🇬🇧 Dan Evans

• # Lloyd Harris