DTI may refer to:
- Debt-to-income ratio
- Deep trench isolation
- Defense Technology Institute, the Thai defense technology public organisation
- Department of Trade and Industry, a government department in several countries
- Detroit, Toledo and Ironton Railroad
- Dial test indicator
- Diffusion tensor imaging
- Direct thrombin inhibitor
- Diversified Technology, Inc.
- diesel turbo injection, on some older Opel models, predecessor of CDTi
- direct tension indicator