The 2004 US Open was held between August 30, 2004 – September 12, 2004.
Both Andy Roddick and Justine Henin-Hardenne were unsuccessful in their title defences, Roddick losing in the quarter-finals to Joachim Johansson and Henin-Hardenne falling in the fourth round to Nadia Petrova. On the men's side, Roger Federer won his first US Open, defeating rival and 2001 champion Lleyton Hewitt in a lopsided final. Svetlana Kuznetsova won the women's title defeating Elena Dementieva in the final.
Roger Federer defeated Lleyton Hewitt, 6–0, 7–6(7–3), 6–0
- • It was Federer's 4th career Grand Slam singles title and his 1st title at the US Open. It was Federer's 9th title of the year, and his 20th overall.
Svetlana Kuznetsova defeated Elena Dementieva, 6–3, 7–5
- • It was Kuznetsova's 1st career Grand Slam singles title.
Mark Knowles / Daniel Nestor defeated Leander Paes / David Rikl, 6–3, 6–3
- • It was Knowles' 2nd career Grand Slam doubles title and his 1st title at the US Open.
- • It was Nestor's 2nd career Grand Slam doubles title and his 1st title at the US Open.
Virginia Ruano Pascual / Paola Suárez defeated Svetlana Kuznetsova / Elena Likhovtseva, 6–4, 7–5
- • It was Ruano Pascual's 7th career Grand Slam doubles title and her 3rd and last title at the US Open.
- • It was Suárez' 7th career Grand Slam doubles title and her 3rd and last title at the US Open.
Vera Zvonareva / Bob Bryan defeated Alicia Molik / Todd Woodbridge, 6–3, 6–4
- • It was Zvonareva's 1st career Grand Slam mixed doubles title.
- • It was Bryan's 2nd career Grand Slam mixed doubles title and his 2nd (consecutive) title at the US Open.
Andy Murray defeated Sergiy Stakhovsky, 6–4, 6–2
Michaëlla Krajicek defeated Jessica Kirkland, 6–1, 6–1
Brendan Evans / Scott Oudsema defeated Andreas Beck / Sebastian Rieschick, 4–6, 6–1, 6–2
Marina Erakovic / Michaëlla Krajicek defeated Mădălina Gojnea / Monica Niculescu, 7–6(7–4), 6–0
- ^ Federer became the first Swiss player to win the US Open men's singles title.
- ^ Andy Murray reached the men's singles final in 2008, and won the men's singles title in 2012.