2005 Australian Open – Men's singles

Marat Safin defeated Lleyton Hewitt in the final, 1–6, 6–3, 6–4, 6–4 to win the men's singles tennis title at the 2005 Australian Open. It was his first Australian Open title (following two runner-up finishes in 2002 and 2004) and second and last major title overall, having previously won the 2000 US Open. Safin saved a match point en route to the title, against Roger Federer in the semifinals. Hewitt was the first Australian to reach the final since Pat Cash in 1988.

Federer was the defending champion, but lost in the semifinals to Safin in a rematch of the previous year's final, despite holding a match point in the fourth set. Federer's loss ended his 26-match winning streak dating to the 2004 US Open.

The final attracted many viewers in Australia (primarily due to the presence of countryman Hewitt), averaging 4.05 million viewers. The viewing audience remains one of the highest in Australian history. The match was broadcast in the host nation by host broadcaster the Seven Network with commentators Bruce McAvaney and two-time champion Jim Courier (in his first appearance on Australian commercial television).

This tournament marked the major main-draw debut of future 10-time Australian Open champion and 24-time major champion Novak Djokovic (who qualified for the main draw before losing to Safin in the first round), and the last Australian Open for four-time champion Andre Agassi. Future 22-time major champion Rafael Nadal advanced beyond the third round of a major for the first time, losing to Hewitt in the fourth round. It was also the last major in which neither Federer, Nadal, nor Djokovic reached the final until the 2014 US Open, a span of 38 events. It remains the only major where Federer, Nadal and Djokovic all competed but none of them reached the final.

Seeds
• # Roger Federer (semifinals)

• # 🇺🇸 Andy Roddick (semifinals)

• # 🇦🇺 Lleyton Hewitt (final)

• # 🇷🇺 Marat Safin (champion)

• # 🇪🇸 Carlos Moyá (first round)

• # 🇦🇷 Guillermo Coria (fourth round)

• # 🇬🇧 Tim Henman (third round)

• # 🇺🇸 Andre Agassi (quarterfinals)

• # 🇦🇷 David Nalbandian (quarterfinals)

• # 🇦🇷 Gastón Gaudio (third round)

• # 🇸🇪 Joachim Johansson (fourth round)

• # 🇦🇷 Guillermo Cañas (fourth round)

• # 🇪🇸 Tommy Robredo (third round)

• # 🇫🇷 Sébastien Grosjean (second round)

• # 🇷🇺 Mikhail Youzhny (second round)

• # 🇩🇪 Tommy Haas (second round)

• # 🇷🇴 Andrei Pavel (second round)

• # Nicolás Massú (second round)

• # 🇺🇸 Vincent Spadea (first round)

• # 🇸🇰 Dominik Hrbatý (quarterfinals)

• # 🇩🇪 Nicolas Kiefer (first round)

• # Ivan Ljubičić (second round)

• # Fernando González (third round)

• # 🇪🇸 Feliciano López (third round)

• # 🇦🇷 Juan Ignacio Chela (third round)

• # 🇷🇺 Nikolay Davydenko (quarterfinals)

• # 🇹🇭 Paradorn Srichaphan (second round)

• # Mario Ančić (third round)

• # 🇺🇸 Taylor Dent (third round)

• # 🇸🇪 Thomas Johansson (fourth round)

• # 🇪🇸 Juan Carlos Ferrero (third round)

• # 🇦🇹 Jürgen Melzer (third round)

Wild cards
• 🇦🇺 Paul Baccanello

• 🇦🇺 Chris Guccione

• 🇦🇺 Nathan Healey

• 🇦🇺 Marc Kimmich

• 🇦🇺 Peter Luczak

• 🇫🇷 Gaël Monfils

• 🇦🇺 Todd Reid

• Wang Yeu-tzuoo

Protected ranking
• 🇦🇺 Scott Draper

• 🇺🇸 Justin Gimelstob

• 🇫🇷 Paul-Henri Mathieu

Qualifiers
• 🇨🇾 Marcos Baghdatis

• 🇮🇹 Daniele Bracciali

• Novak Djokovic

• 🇪🇸 Guillermo García López

•  Roko Karanušić

• 🇩🇪 Dieter Kindlmann

• 🇫🇷 Jean-René Lisnard

• 🇮🇹 Federico Luzzi

• 🇦🇹 Oliver Marach

• 🇫🇷 Olivier Patience

• 🇺🇸 Bobby Reynolds

• 🇫🇷 Florent Serra

• 🇯🇵 Takao Suzuki

•  Janko Tipsarević

•  Melle van Gemerden

• 🇨🇿 Tomáš Zíb

Lucky losers
• 🇩🇪 Björn Phau

• 🇧🇪 Christophe Rochus

Withdrawals
• 🇲🇦 Hicham Arazi → replaced by 🇺🇸 Justin Gimelstob

• 🇲🇦 Younes El Aynaoui → replaced by 🇩🇪 Björn Phau

• 🇫🇷 Nicolas Escudé → replaced by 🇪🇸 Félix Mantilla

• 🇦🇹 Stefan Koubek → replaced by 🇫🇷 Arnaud Clément

• 🇸🇰 Karol Kučera → replaced by 🇮🇹 Davide Sanguinetti

• 🇧🇷 Gustavo Kuerten → replaced by 🇦🇺 Scott Draper

• 🇺🇸 Jeff Morrison → replaced by 🇧🇷 Flávio Saretta

• 🇨🇿 Jiří Novák → replaced by 🇫🇷 Olivier Mutis

• 🇷🇺 Dmitry Tursunov → replaced by 🇪🇸 Nicolás Almagro

• Martin Verkerk → replaced by 🇧🇪 Christophe Rochus