The 2011 Kōfu International Open was a professional tennis tournament played on hard courts. It was the fourth edition of the tournament which was part of the 2011 ITF Women's Circuit. It took place in Kōfu, Yamanashi, Japan between 3 and 9 October 2011.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Thailand | Tamarine Tanasugarn | 93 | 1 | |
 Japan | Erika Sema | 124 | 2 | |
| Thailand | Noppawan Lertcheewakarn | 149 | 3 | |
| Chang Kai-chen | 150 | 4 | ||
 Luxembourg | Mandy Minella | 155 | 5 | |
| Japan | Yurika Sema | 189 | 6 | |
| Japan | Junri Namigata | 198 | 7 | |
| Japan | Aiko Nakamura | 224 | 8 |
The following players received wildcards into the singles main draw:
The following players received entry from the qualifying draw:
Mana Ayukawa Yumi Miyazaki Yuriko Sakai Aki YamasotoSee main article: 2011 Kōfu International Open – Singles. Chang Kai-chen def. Mandy Minella, 6–4, 1–6, 6–4
See main article: 2011 Kōfu International Open – Doubles. Chan Chin-wei / Hsu Wen-hsin def. Remi Tezuka / Akiko Yonemura, 6–3, 6–4