| 2005 US Open | |
|---|---|
| Date | August 29 – September 11 |
| Edition | 125th |
| Category | Grand Slam (ITF) |
| Surface | Hardcourt |
| Location | New York City, U.S. |
| Venue | USTA Billie Jean King National Tennis Center |
| Champions | |
| Men's singles | |
 Roger Federer | |
| Women's singles | |
 Kim Clijsters | |
| Men's doubles | |
 Bob Bryan / Mike Bryan | |
| Women's doubles | |
Lisa Raymond /  Samantha Stosur | |
| Mixed doubles | |
 Daniela Hantuchová /  Mahesh Bhupathi | |
| Wheelchair men's singles | |
 Robin Ammerlaan | |
| Wheelchair women's singles | |
| Esther Vergeer | |
| Wheelchair men's doubles | |
Robin Ammerlaan /  Michaël Jérémiasz | |
| Wheelchair women's doubles | |
| Korie Homan / Esther Vergeer | |
| Boys' singles | |
 Ryan Sweeting | |
| Girls' singles | |
 Victoria Azarenka | |
| Boys' doubles | |
| Alex Clayton / Donald Young | |
| Girls' doubles | |
 Nikola Fraňková /  Alisa Kleybanova | |
The 2005 US Open was the fourth and final Grand Slam of 2005. It was held between August 29, 2005, and September 11, 2005.
Roger Federer was successful in defending his 2004 title, defeating Andre Agassi in the final. Svetlana Kuznetsova was unsuccessful in her title defense, losing in the first round against compatriot Ekaterina Bychkova. Kim Clijsters won her first Grand Slam title after four previous Grand Slam final losses. It was the first of three US Open titles for Clijsters, also winning in 2009 and 2010. This was the first time that future US Open (Tennis) champion Andy Murray was featured in the tournament.