1909 U.S. National Championships (tennis)
| 1909 U.S. National Championships | |
|---|---|
| Date | 17 August – 27 August (M) 21 June – 27 June (W) |
| Edition | 29th |
| Category | Grand Slam |
| Surface | Grass |
| Location | Newport, R.I., United States (M) Philadelphia, PA, United States (W) |
| Champions | |
| Men's singles | |
 William Larned [1] | |
| Women's singles | |
| Hazel Hotchkiss Wightman [1] | |
| Men's doubles | |
| Fred Alexander / Harold Hackett [1] | |
| Women's doubles | |
| Hazel Hotchkiss Wightman / Edith Rotch [1] | |
| Mixed doubles | |
| Hazel Hotchkiss Wightman / Wallace F. Johnson [1] | |
List of champions of the 1909 U.S. National Championships tennis tournament (now known as the US Open). The men's tournament was held from 17 August to 27 August on the outdoor grass courts at the Newport Casino in Newport, Rhode Island. The women's tournament was held from 21 June to 27 June on the outdoor grass courts at the Philadelphia Cricket Club in Philadelphia, PA. It was the 29th U.S. National Championships and the second Grand Slam tournament of the three played that year.
Champions
Men's Singles
William Larned (USA) defeated William Clothier (USA) 6–1, 6–2, 5–7, 1–6, 6–1
Women's Singles
Hazel Hotchkiss Wightman (USA) defeated Maud Barger-Wallach (USA) 6–0, 6–1
Men's doubles
Fred Alexander (USA) / Harold Hackett (USA) defeated Maurice McLoughlin (USA) / George Janes (USA) 6–4, 6–4, 6–0
Women's doubles
Hazel Hotchkiss Wightman (USA) / Edith Rotch (USA) defeated Dorothy Green (USA) / 
Lois Moyes (CAN) 6–1, 6–1
Mixed doubles
Hazel Hotchkiss Wightman (USA) / Wallace F. Johnson (USA) defeated Louise Hammond Raymond (USA) / Raymond Little (USA) 6–2, 6–0