Idi or IDI may refer to:
People Idi Amin (1928–2003), President of Uganda and military officer Idi b. Abin Naggara, 4th century Jewish Babylonian rabbi Idi Othman Guda (1941–2015), Nigerian politician Idi Papez, Austrian 1930s pair skater
Acronym ICT Development Index, an index published by the United Nations International Telecommunication Union Inclusive Development Index, an annual economic index Indian Diamond Institute, school in the fields of diamonds, gems and jewellery in India Industrial Developments International, a privately held real estate investment trust Infectious Diseases Institute, a Ugandan medical organization Institut de Droit International, an organization devoted to the study of international law Interactive Design Institute, Edinburgh, providing online courses in art and design International Diving Institute Israel Democracy Institute, a research center dedicated to strengthening Israeli democracy Israel Diamond Institute, a non-profit public interest company in Israel
Other uses Idi language, a language of Papua New Guinea Iði or Idi, a giant in Norse mythology IDI, IATA code for Indiana County–Jimmy Stewart Airport, a business service airport in Indiana, Pennsylvania