1949 U.S. National Championships – Women's singles

Second-seeded Margaret Osborne duPont defeated Doris Hart 6–4, 6–1 in the final to win the women's singles tennis title at the 1949 U.S. National Championships.

Seeds
The tournament used two lists of seven players for seeding the women's singles event; one for U.S. players and one for foreign players. Margaret Osborne duPont is the champion; others show in brackets the round in which they were eliminated.

1. 🇺🇸 Louise Brough (semifinals)

2. 🇺🇸 Margaret Osborne duPont (champion)

3. 🇺🇸 Doris Hart (finalist)

4. 🇺🇸 Shirley Fry (third round)

5. 🇺🇸 Pat Canning Todd (quarterfinals)

6. 🇺🇸 Gussy Moran (third round)

7. 🇺🇸 Beverly Baker (quarterfinals)

1. 🇬🇧 Betty Hilton (semifinals)

2. Magda Rurac (third round)

3. 🇬🇧 Jean Quertier (third round)

4. 🇬🇧 Jean Walker-Smith (third round)

5. 🇬🇧 Kay Tuckey (third round)

6. 🇬🇧 Molly Blair (third round)

7. 🇨🇦 Patricia Macken (first round)

Key

 * Q = Qualifier
 * WC = Wild card
 * LL = Lucky loser
 * r = Retired