EKU or Eku may refer to:
- Eku, Delta, a town in Nigeria
- Eku Edewor (born 1986), Nigerian actress
- Earliest known use, in philately
- Eastern Kentucky University, a public, regional comprehensive, post-secondary institution in Richmond, Kentucky, United States
- European Karate Union, now the European Karate Federation
- Evangelical Church of the Union (Template:Langx), a defunct German Christian denomination
- EKU, a former German brewery, now a brand of Kulmbacher Brewery
- Extended Key Usage, an extension of Public Key Infrastructure to a Digital signature