| 2004 Australian Open | |
|---|---|
| Date | 19 January – 1 February 2004 |
| Edition | 92nd |
| Category | Grand Slam (ITF) |
| Surface | Hardcourt (Rebound Ace) |
| Location | Melbourne, Australia |
| Venue | Melbourne Park |
| Champions | |
| Men's singles | |
.svg.png.webp){kind=small} Roger Federer | |
| Women's singles | |
.svg.png.webp){kind=small} Justine Henin-Hardenne | |
| Men's doubles | |
 Michaël Llodra / Fabrice Santoro | |
| Women's doubles | |
 Virginia Ruano Pascual /  Paola Suárez | |
| Mixed doubles | |
 Elena Bovina / .svg.png.webp){kind=small} Nenad Zimonjić | |
| Wheelchair men's singles | |
.svg.png.webp){kind=small} David Hall | |
| Wheelchair women's singles | |
 Esther Vergeer | |
| Wheelchair men's doubles | |
Robin Ammerlaan /  Martin Legner | |
| Wheelchair women's doubles | |
| Maaike Smit / Esther Vergeer | |
| Boys' singles | |
| Gaël Monfils | |
| Girls' singles | |
 Shahar Pe'er | |
| Boys' doubles | |
 Scott Oudsema / Brendan Evans | |
| Girls' doubles | |
 Chan Yung-jan /  Sun Sheng-Nan | |
The 2004 Australian Open was a Grand Slam tennis tournament held in Melbourne, Australia from 19 January to 1 February 2004.
Andre Agassi was unsuccessful in defending his 2003 title, being defeated in the semi-finals by Marat Safin. This ended a 26-match winning streak for Agassi at the Australian Open, having previously won in 2000, 2001 and 2003, missing 2002 through injury. Roger Federer won his first Australian Open title, defeating Safin in the final. Serena Williams was unable to defend her 2003 title after withdrawing from the tournament due to a left knee injury. Justine Henin-Hardenne defeated compatriot and rival Kim Clijsters in the final to win her only Australian Open title.
Seniors
Men's singles
Roger Federer[1] defeated Marat Safin, 7–6(7–3), 6–4, 6–2
- It was Federer's 1st title of the year, and his 12th overall. It was his 2nd career Grand Slam title, and his 1st Australian Open title.
Women's singles
Justine Henin-Hardenne[2] defeated Kim Clijsters, 6–3, 4–6, 6–3
- It was Henin-Hardenne's 2nd title of the year, and her 16th overall. It was her 3rd career Grand Slam title, and her 1st Australian Open title.
Men's doubles
Michaël Llodra / Fabrice Santoro defeated Bob Bryan / Mike Bryan, 7–6(7–4), 6–3
- It was Llodra's 2nd career Grand Slam doubles title and his 2nd (consecutive) at the Australian Open.
- It was Santoro's 2nd career Grand Slam doubles title and his 2nd (consecutive) at the Australian Open.
Women's doubles
Virginia Ruano / Paola Suárez defeated Svetlana Kuznetsova / Elena Likhovtseva, 6–4, 6–3
Mixed doubles
Elena Bovina / Nenad Zimonjić defeated Martina Navratilova / 
Leander Paes, 6–1, 7–6(7–3)
- It was Bovina's 1st career Grand Slam mixed doubles title.
- It was Zimonjić's 1st career Grand Slam mixed doubles title.
Juniors
Boys' singles
Gaël Monfils defeated Josselin Ouanna, 6–0, 6–3
Girls' singles
Shahar Pe'er defeated 
Nicole Vaidišová, 6–1, 6–4
Boys' doubles
Scott Oudsema / Brendan Evans defeated David Galić / David Jeflea, 6–1, 6–1
Girls' doubles
Chan Yung-jan / Sun Shengnan defeated Veronika Chvojková / Nicole Vaidišová, 7–5, 6–3
Wheelchair
Men's singles
David Hall defeated Robin Ammerlaan, 6–4, 7–5
Women's singles
Esther Vergeer defeated Daniela Di Toro, 4–6, 6–3, 6–1
Men's doubles
Robin Ammerlaan / Martin Legner defeated 
Tadeusz Kruszelnicki / 
Satoshi Saida, 6–3, 6–3
Women's doubles
Maaike Smit / Esther Vergeer defeated Sonja Peters / Sharon Walraven, 6–3, 7–6(3)