2015 Keio Challenger – Singles

The Keio Challenger is a professional tennis tournament played on hardcourts. It is currently part of the ATP Challenger Tour and the ITF Women's Circuit. Having been held in Yokohama, Japan since 1999. In 2015, Taro Daniel won the men's singles title, defeating Go Soeda in the final 4–6, 6–3 , 6–3.

Seeds
• # 🇦🇺 John Millman (first round)

• # 🇦🇺 Matthew Ebden (semifinals)

• # 🇯🇵 Tatsuma Ito (semifinals)

• # 🇯🇵 Go Soeda (final)

• # 🇯🇵 Taro Daniel (champion)

• # 🇯🇵 Yūichi Sugita (quarterfinals)

• # 🇷🇺 Konstantin Kravchuk (second round)

• # 🇯🇵 Yoshihito Nishioka (quarterfinals)