| Champ: |  Lindsay Davenport |
| Runner: | Monica Seles |
| Score: | 6–7(6–8), 6–1, 6–2 |
| Type: | women |
| Draw: | 28 (4 / 3) |
| Seeds: | 8 |
| Before Name: | Toray Pan Pacific Open – Singles |
| After Name: | Toray Pan Pacific Open – Singles |
| Main Name: | Pan Pacific Open |
See main article: article and 2003 Toray Pan Pacific Open.
Lindsay Davenport defeated Monica Seles in the final, 6–7(6–8), 6–1, 6–2 to win the singles tennis title at the 2003 Pan Pacific Open. It was her first title of the season, and the 38th of her career.[1] [2]
Martina Hingis was the reigning champion, but did not compete this year. Hingis would retire from professional tennis one month later.[3]
The first four seeds received a bye into the second round.