Keio University (慶應義塾大学, Keiō Gijuku Daigaku), abbreviated as Keio (慶應) or Keidai (慶大), is a private research university located in Minato, Tokyo, Japan. It was originally established as a school for Western studies in 1858 in Edo. It was granted university status in 1920, becoming one of the first private universities in the country.

Keio University is also one of the member universities of RU11 and APRU, and it is one of two Japanese universities (alongside the University of Tokyo) to be a member of the World Economic Forum's Global University Leaders Forum.