IDG or IdG may refer to:
- IDG Ventures, a family of venture funds originally funded by International Data Group
- Apple Industrial Design Group, part of Apple Inc.
- Indigo Books and Music, a Canadian retail bookstore chain
- Industrial Development Group, a South African mining company headed by Makaziwe Mandela
- International Deployment Group, a department of the Australian Federal Police
- International Data Group, an American technology, media, research, event management, and venture capital organization.
- Integrated Drive Generator, an aircraft electrical generation unit
- The IATA code for Ida Grove Municipal Airport, an airport in Iowa, USA
- Infinite derivative gravity, a theory of modified gravity