Boris Becker defeated the two-time defending champion Ivan Lendl in the final, 1–6, 6–4, 6–4, 6–4 to win the men's singles tennis title at the 1991 Australian Open. It was his first Australian Open title and fifth major singles title overall.

Seeds

🇸🇪 Stefan Edberg (semifinals) 🇩🇪 Boris Becker (champion) Ivan Lendl (final) 🇺🇸 Pete Sampras (withdrew because of shin splints) Goran Ivanišević (third round) 🇪🇸 Emilio Sánchez (first round) 🇺🇸 Brad Gilbert (third round) 🇸🇪 Jonas Svensson (third round) Andrei Chesnokov (first round) 🇫🇷 Guy Forget (quarterfinals) Jakob Hlasek (first round) 🇺🇸 Jay Berger (third round) 🇺🇸 Aaron Krickstein (fourth round) Andrei Cherkasov (second round) Marc Rosset (first round) 🇺🇸 Jim Courier (fourth round)

Qualifying

Draw

Finals

Top half

Section 1

Section 2

Section 3

Section 4

Bottom half

Section 5

Section 6

Section 7

Section 8