2018 Toray Pan Pacific Open – Singles

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.

Seeds
The top four seeds received a bye into the second round. • # Caroline Wozniacki (second round)

• # 🇫🇷 Caroline Garcia (quarterfinals)

• # 🇯🇵 Naomi Osaka (final)

• # 🇨🇿 Karolína Plíšková (champion)

• # 🇺🇸 Sloane Stephens (first round)

• # 🇪🇸 Garbiñe Muguruza (second round)

• # 🇦🇺 Ashleigh Barty (second round)

• # 🇨🇿 Barbora Strýcová (quarterfinals)

Seeds
• #🇰🇿 Zarina Diyas (qualified)

• # 🇵🇱 Magda Linette (qualifying competition)

• #🇺🇸 Alison Riske (qualified)

• #🇨🇦 Eugenie Bouchard (qualified)

• # 🇨🇳 Duan Yingying (withdrew)

• # Jana Fett (first round)

• #🇯🇵 Nao Hibino (qualified)

• # 🇩🇪 Antonia Lottner (qualifying competition)

• #🇯🇵 Misaki Doi (qualified)

• # 🇯🇵 Miyu Kato (withdrew)

• # 🇯🇵 Ayano Shimizu (qualifying competition)

• # 🇩🇪 Anna Zaja (first round)

Qualifiers
• #🇰🇿 Zarina Diyas

• #🇯🇵 Nao Hibino

• #🇺🇸 Alison Riske

• #🇨🇦 Eugenie Bouchard

• #🇨🇦 Gabriela Dabrowski

• #🇯🇵 Misaki Doi