TNI may refer to:
- Satna Airport, IATA code TNI
- Tahitian Noni International, Inc.
- Taqramiut Nipingat Inc., an Inuit broadcasting organization in Quebec, Canada
- Telephone Network Interface; see Network interface device (NID)
- Tentara Nasional Indonesia (Indonesian); see Military of Indonesia.
- Texas Neurosciences Institute, a research and neurological clinical center
- Thai-Nichi Institute of Technology a private college in Thailand
- Transnational Institute, an international think tank for progressive politics
- Transnationality Index
- The New Inquiry
- The Next Idea