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-breaking 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 became the first Greek player to reach the semifinals at a singles major, after becoming the first man representing Greece to win a main-draw singles match at the Australian Open.

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.