| 1990 US Open | |
|---|---|
| Date | August 27 – September 9 |
| Edition | 110th |
| Category | Grand Slam (ITF) |
| Surface | Hardcourt |
| Location | New York City, New York, United States |
| Champions | |
| Men's singles | |
 Pete Sampras | |
| Women's singles | |
 Gabriela Sabatini | |
| Men's doubles | |
.svg.png.webp){kind=small} Pieter Aldrich / Danie Visser | |
| Women's doubles | |
| Gigi Fernández / Martina Navratilova | |
| Mixed doubles | |
.svg.png.webp){kind=small} Elizabeth Smylie / Todd Woodbridge | |
| Boys' singles | |
 Andrea Gaudenzi | |
| Girls' singles | |
 Magdalena Maleeva | |
| Boys' doubles | |
.svg.png.webp){kind=small} Sébastien Leblanc / Greg Rusedski | |
| Girls' doubles | |
| Kristin Godridge / Kirrily Sharpe | |
The 1990 US Open was a tennis tournament played on outdoor hard courts at the USTA National Tennis Center in New York City in the United States. It was the 110th edition of the US Open and was held from August 27 to September 9, 1990.
Seniors
Men's singles
Pete Sampras defeated Andre Agassi 6–4, 6–3, 6–2
- It was Pete Sampras' 1st career Grand Slam title and his 1st US Open title. He became the youngest US Open men's singles champion at 19 years, 28 days.
Women's singles
Gabriela Sabatini defeated 
Steffi Graf 6–2, 7–6(7–4)
- It was Sabatini's only Grand Slam title. She became the first female tennis player from Argentina to win a Grand Slam singles title.
Men's doubles
Pieter Aldrich / Danie Visser defeated Paul Annacone / David Wheaton 6–2, 7–6 (7–3), 6–2
- It was Pieter Aldrich's 2nd and last career Grand Slam title and his only US Open title. It was Danie Visser's 2nd career Grand Slam title and his only US Open title.
Women's doubles
Gigi Fernández / Martina Navratilova defeated 
Jana Novotná / Helena Suková 6–2, 6–4
- It was Gigi Fernández's 2nd career Grand Slam title and her 2nd US Open title. It was Martina Navratilova's 55th career Grand Slam title and her 15th US Open title.
Mixed doubles
Elizabeth Smylie / Todd Woodbridge defeated 
Natasha Zvereva / Jim Pugh 6–4, 6–2
- It was Elizabeth Smylie's 3rd career Grand Slam title and her 2nd and last US Open title. It was Todd Woodbridge's 1st career Grand Slam title and his 1st US Open title.
Juniors
Boys' singles
Andrea Gaudenzi defeated 
Mikael Tillström 6–2, 4–6, 7–6
Girls' singles
Magdalena Maleeva defeated 
Noëlle van Lottum 7–5, 6–2
Boys' doubles
Sébastien Leblanc / Greg Rusedski defeated Marten Renström / Mikael Tillström 6–7, 6–3, 6–4
Girls' doubles
Kristin Godridge / Kirrily Sharpe defeated Erika deLone / Lisa Raymond 4–6, 7–5, 6–2
Other events
Gentlemen's invitation singles
Sandy Mayer defeated Tom Gullikson 6–4, 6–4
Gentlemen's invitation doubles
Tom Gullikson / Dick Stockton defeated Mark Edmondson / Sherwood Stewart 6–7, 7–6, 6–4
Ladies' invitation doubles
Rosemary Casals / Billie Jean King defeated Wendy Turnbull / 
Virginia Wade 2–6, 6–4, 6–3
Prize money
| Event | W | F | SF | QF | 4R | 3R | 2R | 1R | |
| Singles [1] | Men | $350,000 | $175,000 | $87,000 | $45,378 | $24,590 | $14,166 | $8,697 | $5,195 |
| Women | $350,000 | $175,000 | $87,000 | $45,378 | $24,590 | $14,166 | $8,697 | $5,195 | |
Total prize money for the event was $6,349,250.