| 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 | |
 Roger Federer | |
| Women's singles | |
 Justine Henin-Hardenne | |
| Men's doubles | |
 Michaël Llodra / Fabrice Santoro | |
| Women's doubles | |
 Virginia Ruano Pascual /  Paola Suárez | |
| Mixed doubles | |
 Elena Bovina /  Nenad Zimonjić | |
| Wheelchair men's singles | |
 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.