Keio (disambiguation)

Keio may refer to:

• Keiō (慶応), a Japanese era name
• Keio University (慶應義塾大学), a Tokyo University
• Keio Corporation (京王電鉄), a Tokyo-based transportation company
  • See under 'Keio...' in Category:Electric multiple units of Japan
• Keio Flying Squadron series or Keio Yuugekitai, the name of a video game series released on the Sega Mega CD\Sega CD, Sega Saturn, and Sony PlayStation consoles