Defending champion Roger Federer defeated Marin Čilić in the final, 6–2, 6–7(5–7), 6–3, 3–6, 6–1 to win the men's singles tennis title at the 2018 Australian Open.

[2] Čilić was the first Croatian to reach an Australian Open singles final.

[3] This was the first time since the 2008 Wimbledon Championships that two unseeded players (Chung Hyeon and Kyle Edmund) reached the semifinals of a men's singles major, and the first time at the Australian Open since 1999.

[4] Chung became the first South Korean player to reach a major quarterfinal and semifinal.

[6] Click on the seed number of a player to go to their draw section.