A Mii is a personalized digital avatar for the Wii video game console by Nintendo. MII or Mii may also refer to:
- 1002, the year or the number in Roman numerals
- Major Industry Identifier, part of ISO 7812
- Maritime Institute of Ireland, who operate the National Maritime Museum of Ireland
- Media Independent Interface, in Ethernet hardware
- Michigan Interactive Investments, a University of Michigan student-run finance and investment organization
- Mii (Jungle de Ikou!), the busty Goddess of Fertility in Jungle de Ikou! (a fanservice anime)
- MII (cost-estimating-software), developed for the United States Army Corps of Engineers by Project Time & Cost, Inc.
- MII (videocassette format), a professional videotape format developed by Panasonic
- MII (Cyrix CPU), an x86 architecture CPU by Cyrix
- Mineral Information Institute, an American educational institute dedicated to teaching schoolchildren about natural resources
- Ministry of Information Industry, a ministry of the State Council of the People's Republic of China
