The 1939 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 September 7 until September 17. It was the 59th staging of the U.S. National Championships and the fourth Grand Slam tennis event of the year.

Finals

Men's singles

🇺🇸 Bobby Riggs defeated 🇺🇸 Welby van Horn 6–4, 6–2, 6–4

Women's singles

🇺🇸 Alice Marble defeated 🇺🇸 Helen Jacobs 6–0, 8–10, 6–4

Men's doubles

🇦🇺 Adrian Quist / 🇦🇺 John Bromwich defeated 🇦🇺 Jack Crawford / 🇦🇺 Harry Hopman 8–6, 6–1, 6–4

Women's doubles

🇺🇸 Sarah Palfrey / 🇺🇸 Alice Marble defeated 🇬🇧 Kay Stammers / 🇬🇧 Freda James Hammersley 7–5, 8–6

Mixed doubles

🇺🇸 Alice Marble / 🇦🇺 Harry Hopman defeated 🇺🇸 Sarah Palfrey / 🇺🇸 Elwood Cooke 9–7, 6–1