| 1958 U.S. National Championships | |
|---|---|
| Date | 29 August – 7 September | 
| Edition | 78th | 
| Category | Grand Slam (ILTF) | 
| Surface | Grass | 
| Location | Forest Hills, Queens New York City, New York | 
| Venue | West Side Tennis Club | 
| Champions | |
| Men's singles | |
|  Ashley Cooper  [1] | |
| Women's singles | |
|  Althea Gibson | |
| Men's doubles | |
|  Alex Olmedo /  Ham Richardson | |
| Women's doubles | |
|  Jeanne Arth /  Darlene Hard | |
| Mixed doubles | |
|  Margaret Osborne /  Neale Fraser | |
The 1958 U.S. National Championships (now known as the US Open) was a tennis tournament that took place on the outdoor grass courts at the West Side Tennis Club, Forest Hills in New York City, New York. The tournament ran from 29 August until 7 September. It was the 78th staging of the U.S. National Championships, and the fourth Grand Slam tennis event of the year.
  Ashley Cooper defeated
  Ashley Cooper defeated   Malcolm Anderson  6–2, 3–6, 4–6, 10–8, 8–6
  Malcolm Anderson  6–2, 3–6, 4–6, 10–8, 8–6
  Althea Gibson defeated
  Althea Gibson defeated   Darlene Hard 3–6, 6–1, 6–2
  Darlene Hard 3–6, 6–1, 6–2
  Alex Olmedo (USA) /
  Alex Olmedo (USA) /   Ham Richardson (USA) defeated
  Ham Richardson (USA) defeated   Sam Giammalva (USA) /
  Sam Giammalva (USA) /   Barry MacKay (tennis) (USA) 3–6, 6–3, 6–4, 6–4  [2]
  Barry MacKay (tennis) (USA) 3–6, 6–3, 6–4, 6–4  [2] 
  Jeanne Arth (USA) /
  Jeanne Arth (USA) /   Darlene Hard (USA) defeated
  Darlene Hard (USA) defeated   Althea Gibson (USA) /
  Althea Gibson (USA) /   Maria Bueno (BRA) 2–6, 6–3, 6–4  [3]
  Maria Bueno (BRA) 2–6, 6–3, 6–4  [3] 
  Margaret Osborne (USA) /
  Margaret Osborne (USA) /    Neale Fraser (AUS) defeated
  Neale Fraser (AUS) defeated   Maria Bueno (BRA) /
  Maria Bueno (BRA) /   Alex Olmedo (USA) 6–4, 3–6, 9–7  [4]
  Alex Olmedo (USA) 6–4, 3–6, 9–7  [4]