2019 Australian Open – Men's singles

Novak Djokovic defeated Rafael Nadal in the final, 6–3, 6–2, 6–3 to win the men's singles tennis title at the 2019 Australian Open. It was his record seventh Australian Open title and 15th major title overall, surpassing Pete Sampras for third place on the all-time list. Djokovic and Nadal were both in contention for the world No. 1 singles ranking; Djokovic retained the top ranking by reaching the fourth round. Nadal was attempting to become the first man in the Open Era to achieve a double career Grand Slam, a feat he would achieve three years later.

Roger Federer was the two-time defending champion, but lost in the fourth round to Stefanos Tsitsipas. Tsitsipas was the first Greek player to reach the semifinals at a singles major.

This was the first Australian Open since 1982 to feature a final set tie-break. Upon reaching 6–6 in the fifth set, a match tie-break is played where the winner is the first to reach ten points and lead by two points. The first men's singles main-draw match to feature the ten-point tiebreak was the first-round match between Jérémy Chardy and Ugo Humbert.