KIR, Kir or kir may refer to:
- Kir (river), in northern Albania
- Kiribati, officially known as the Republic of Kiribati
- Kyrgyz language
- Al Karak, biblical town of Kir
- Kir of Moab, biblical stronghold
- IATA code for Kerry Airport in Ireland
- Kir (cocktail), alcoholic beverage
- Killer-cell immunoglobulin-like receptor, a class of receptors on the surface of natural killer cells
- Kir Bulychev, Russian science fiction writer and historian
- Kir, a fictional character in the series Case Closed
- Kir, inwardly-rectifying potassium channels