| 1984 US Open | |
|---|---|
| Date | August 28 – September 9 |
| Edition | 104th |
| Category | Grand Slam (ITF) |
| Surface | Hardcourt |
| Location | New York City, New York, United States |
| Champions | |
| Men's singles | |
 John McEnroe | |
| Women's singles | |
| Martina Navratilova | |
| Men's doubles | |
 John Fitzgerald /  Tomáš Šmíd | |
| Women's doubles | |
| Martina Navratilova / Pam Shriver | |
| Mixed doubles | |
 Manuela Maleeva / Tom Gullikson | |
| Boys' singles | |
| Mark Kratzmann | |
| Girls' singles | |
| Katerina Maleeva | |
| Boys' doubles | |
 Leonardo Lavalle /  Mihnea-Ion Năstase | |
| Girls' doubles | |
 Mercedes Paz / Gabriela Sabatini | |
The 1984 US Open was a tennis tournament played on outdoor hard courts at the USTA National Tennis Center in New York City in New York in the United States. It was the 104th edition of the US Open and was held from August 28 to September 9, 1984.