2018 İstanbul Cup – Singles

Elina Svitolina was the defending champion, but chose to compete in Stuttgart instead.

Pauline Parmentier won the title, her first since 2008, defeating Polona Hercog in the final, 6–4, 3–6, 6–3.

Seeds
• # Caroline Wozniacki (quarterfinals, retired)

• #🇷🇺 Svetlana Kuznetsova (quarterfinals)

• #🇵🇱 Agnieszka Radwańska (first round, retired)

• #🇨🇳 Zhang Shuai (first round)

• #🇷🇺 Ekaterina Makarova (first round)

• #🇷🇴 Sorana Cîrstea (first round)

• #🇷🇴 Irina-Camelia Begu (semifinals)

• #🇧🇾 Aryna Sabalenka (first round)

Seeds
• # Richèl Hogenkamp (qualifying competition)

• # 🇷🇺 Evgeniya Rodina (first round)

• # 🇲🇪 Danka Kovinić (qualified)

• # Arantxa Rus (qualified)

• # Dalila Jakupović (qualified)

• # 🇪🇸 Sara Sorribes Tormo (qualifying competition)

• # 🇨🇿 Barbora Krejčíková (qualifying competition)

• # 🇷🇺 Anna Kalinskaya (qualified)

• # 🇨🇿 Tereza Martincová (first round)

• # 🇧🇬 Viktoriya Tomova (qualified)

• # 🇯🇵 Misaki Doi (first round)

• # 🇷🇴 Alexandra Dulgheru (first round)

Qualifiers
• # 🇧🇬 Viktoriya Tomova

• # 🇷🇺 Valentyna Ivakhnenko

• # 🇲🇪 Danka Kovinić

• # Arantxa Rus

• # Dalila Jakupović

• # 🇷🇺 Anna Kalinskaya