OIT may refer to:

• Operator Interface Terminal, in industrial design (see user interface)
• Order-independent transparency, in computer graphics

• Oral immunotherapy, oral feeding of allergen to raise allergic threshold

• Out of India Theory, the idea that the Aryans are indigenous to the Indian subcontinent
• Oxidative-induction time, a standardized test which measures the level of thermal stabilization

• Oita Airport, Kunisaki, Oita Prefecture, Japan (by IATA airport code)

• Osaka Institute of Technology, Osaka, Japan
• Oregon Institute of Technology, Oregon, United States
• Oriental Institute of Technology, a university in New Taipei, Taiwan