CMI may refer to:
- Medical
- Case mix index
- Cell-mediated immunity
- Chronic Mental Illness
- Companies
- C-Media Electronics, Inc., Taiwanese computer hardware company
- Chimei InnoLux Corporation, Taiwanese TFT-LCD panel manufacturer
- Cockerill Maintenance & Ingénierie, Belgian engineering company
- Computer Memories Inc., a defunct hard disk drive manufacturer
- Cummins, Inc., a manufacturer of diesel engines
- Economics and finance
- Chiang Mai Initiative, currency swap among ASEAN+3 countries
- CMI Gold & Silver Inc.
- Credit Managers' Index, an economic indicator tracking the manufacturing and service sectors
- Science and computing
- Canis Minor astronomical constellation abbreviation "CMa", as standardized by the International Astronomical Union
- Coded Mark Inversion
- Content Management Interface
- Organizations and institutes
- Cambridge-MIT Institute
- Carmelites of Mary Immaculate
- Chartered Management Institute
- Chennai Mathematical Institute
- Chinese Maritime Institute
- Chr. Michelsen Institute
- Clay Mathematics Institute
- The College of the Marshall Islands, www.cmi.edu
- Committee for a Marxist International
- Creation Ministries International
- Crisis Management Initiative
- Culture and Media Institute
- University of Illinois Willard Airport, IATA airport code (and alias for the Champaign-Urbana Metropolitan Area)
- Other
- 901, as Roman numerals
- Certified Master Inspector
- Continental Micronesia, which has the ICAO Code CMI
- The Curse of Monkey Island
- Fairlight CMI, Fairlight Computer Musical Instrument