The 1949 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, United States. The tournament ran from August 26 until September 5. It was the 69th staging of the U.S. National Championships, and the fourth Grand Slam tennis event of the year. Pancho Gonzales won his second and final Grand Slam title before turning professional.

Finals

Men's singles

🇺🇸 Pancho Gonzales defeated 🇺🇸 Ted Schroeder 16–18, 2–6, 6–1, 6–2, 6–4

Women's singles

🇺🇸 Margaret Osborne duPont defeated 🇺🇸 Doris Hart 6–4, 6–1

Men's doubles

🇦🇺 John Bromwich / 🇦🇺 Bill Sidwell defeated 🇦🇺 Frank Sedgman / 🇦🇺 George Worthington 6–4, 6–0, 6–1

Women's doubles

🇺🇸 Louise Brough / 🇺🇸 Margaret Osborne duPont defeated 🇺🇸 Shirley Fry / 🇺🇸 Doris Hart 6–4, 10–8

Mixed doubles

🇺🇸 Louise Brough / Eric Sturgess defeated 🇺🇸 Margaret Osborne duPont / 🇺🇸 Bill Talbert 4–6, 6–3, 7–5