IHI can refer to:

• Ifakara Health Institute, a health research organization in Tanzania
• Information Holdings Inc., part of The Thomson Corporation since 2004
• Institute for Healthcare Improvement
• IHI Corporation, formerly known as Ishikawajima-Harima Heavy Industries, a Japanese company which produces ships, aero-engines, and other machinery
• Ice Hockey Iceland, ÍHÍ (Icelandic: Íshokkísamband Íslands)