1911 U.S. National Championships
Date	August 21 – September 3 (M) June 12 – 17 (W)
Edition	31st
Category	Grand Slam
Surface	Grass (outdoor)
Location	Newport, R.I., United States (M) Philadelphia, PA, United States (W)
Venue	Newport Casino (M) Philadelphia Cricket Club (W)
Champions
Men's singles
William Larned[1]
Women's singles
Hazel Hotchkiss[1]
Men's doubles
Raymond Little / Gustav Touchard[2]
Women's doubles
Hazel Hotchkiss / Eleonora Sears[3]
Mixed doubles
Hazel Hotchkiss / Wallace F. Johnson[4]
← 1910 · U.S. National Championships · 1912 →

The 1911 U.S. National Championships (now known as the US Open) took place on the outdoor grass courts at the Newport Casino in Newport, United States. The men's singles tournament ran from August 21 until September 3 while the women's singles and doubles championship took place from June 12 to June 17 at the Philadelphia Cricket Club in Chestnut Hill. It was the 31st staging of the U.S. National Championships, and the second Grand Slam tennis event of the year. William Larned won the men's singles championship for a record seventh and final time.

Finals

Men's singles

William Larned (USA) defeated Maurice McLoughlin (USA) 6–4, 6–4, 6–2

Women's singles

Hazel Hotchkiss (USA) defeated Florence Sutton (USA) 8–10, 6–1, 9–7

Men's doubles

Raymond Little (USA) / Gustav Touchard (USA) defeated Fred Alexander (USA) / Harold Hackett (USA) 7–5, 13–15, 6–2, 6–4

Women's doubles

Hazel Hotchkiss (USA) / Eleonora Sears (USA) defeated Dorothy Green (USA) / Florence Sutton (USA) 6–4, 4–6, 6–2

Mixed doubles

Hazel Hotchkiss (USA) / Wallace F. Johnson (USA) defeated Edna Wildey (USA) / Herbert M. Tilden (USA) 6–4, 6–4