The 1945 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 28 until September 3. It was the 65th staging of the U.S. National Championships, and due to World War II it was the only Grand Slam tennis event of the year.[1]
| 1945 U.S. National Championships | |
|---|---|
| Date | August 28 – September 3 |
| Edition | 65th |
| Category | Grand Slam (ILTF) |
| Surface | Grass |
| Location | Forest Hills, Queens New York City, United States |
| Venue | West Side Tennis Club |
| Champions | |
| Men's singles | |
 Frank Parker | |
| Women's singles | |
| Sarah Palfrey Cooke | |
| Men's doubles | |
| Gardnar Mulloy / Bill Talbert | |
| Women's doubles | |
| Louise Brough / Margaret Osborne | |
| Mixed doubles | |
| Margaret Osborne / Bill Talbert | |
Finals edit
Men's singles edit
Frank Parker defeated William Talbert 14–12, 6–1, 6—2
Women's singles edit
Sarah Palfrey Cooke defeated Pauline Betz 3–6, 8–6, 6–4
Men's doubles edit
Gardnar Mulloy / Bill Talbert defeated 
Bob Falkenburg / Jack Tuero 12–10, 8–10, 12–10, 6–2 [2]
Women's doubles edit
Louise Brough / Margaret Osborne defeated Pauline Betz / Doris Hart 6–3, 6–3 [3]
Mixed doubles edit
Margaret Osborne / Bill Talbert defeated Doris Hart / Bob Falkenburg 6–4, 6–4 [4]