NGI may refer to:
- Next Generation Internet (disambiguation)
- National Gallery of Ireland
- National Genetics Institute
- Northern Gulf Institute
- Norwegian Geotechnical Institute
- Navigazione Generale Italiana
- Next Generation Identification
- Nationaal Geografisch Instituut - Institut Géographique National - The Belgian national geographic institute, often referred to by the abbreviation 'NGI' in Dutch and 'IGN' in French
- Not guilty by reason of insanity, for which the abbreviation 'NGRI' is also used