FDI may refer to:

• fDi magazine, a British foreign direct investment publication
• Federal Deposit Insurance Corporation, a United States government corporation
• Foreign direct investment, purchase of an asset in a country by another country's company

• Field Device Integration, an International Electrotechnical Commission standards
• Flexible Display Interface
• Formatted Disk Image, part of the Unified emulator format

• FDI World Dental Federation
• First dorsal interosseous, muscle in the hand

• Fault detection and isolation, in control engineering
• Brothers of Italy (FdI, from the Italian name Fratelli d'Italia), an Italian political party
• Films Division of India, a government-owned film production company in India
• Foundation for Democracy in Iran, a US-based Iranian dissident organization
• Frégate de défense et d'intervention, a class of frigates of the French Navy