| Champ: |  Karolína Plíšková |
| Runner: |  Naomi Osaka |
| Score: | 6–4, 6–4 |
| Type: | singles doubles |
| Before Name: | Toray Pan Pacific Open – Singles |
| After Name: | Toray Pan Pacific Open – Singles |
See main article: article and 2018 Toray Pan Pacific Open.
Caroline Wozniacki was the two-time defending champion, but lost in the second round to Camila Giorgi.
Karolína Plíšková won the title, defeating Naomi Osaka in the final, 6–4, 6–4. Plíšková won the title after saving two match points Alison Riske had against her in the quarterfinals.
The top four seeds received a bye into the second round.