UIA can refer to:
- Inter-American University (Universidad Interamericana de Puerto Rico)
- Ukrainian Insurgent Army
- Ukraine International Airlines
- Universiti Islam Antarabangsa
- Union of International Associations
- United International Airlines, a Serbian cargo airline
- United Iraqi Alliance
- Universidad Iberoamericana in Mexico
- International Union of Architects (Union internationale des Architectes)
- Argentine Industrial Union (Unión Industrial Argentina)
- Union Internationale des Avocats
- Universitaire Instelling Antwerpen
- United Israel Appeal (Keren Hayesod - United Israel Appeal)
- United Israel Appeal, Inc.
- Unmanaged Internet Architecture
- UI Automation, a Microsoft computer accessibility technology
- UIA (Insurance), in the United Kingdom