| 2009 Keio Challenger | |
|---|---|
| Date | 16–22 November |
| Edition | 7th |
| Location | Yokohama, Japan |
| Champions | |
| Singles | |
 Takao Suzuki | |
| Doubles | |
 Yang Tsung-hua / Yi Chu-huan | |
The 2009 Keio Challenger was a professional tennis tournament played on outdoor hard courts. It was the seventh edition of the tournament which was part of the 2009 ATP Challenger Tour. It took place in Yokohama, Japan between 16 and 22 November 2009.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
| JPN | Go Soeda | 152 | 1 |
 KOR | Im Kyu-tae | 160 | 2 |
 GER | Dieter Kindlmann | 184 | 3 |
| JPN | Tatsuma Ito | 234 | 4 |
 AUT | Philipp Oswald | 235 | 5 |
 SVK | Pavol Červenák | 242 | 6 |
 AUS | Nick Lindahl | 260 | 7 |
| AUT | Martin Fischer | 267 | 8 |
The following players received wildcards into the singles main draw:
The following players received entry from the qualifying draw:
Takao Suzuki def. Martin Fischer, 6–4, 7–6(5)
Yang Tsung-hua / Yi Chu-huan def. 
Alexey Kedryuk / Junn Mitsuhashi, 6–7(9), 6–3, [12–10]
