Yi may mean:
- Yi Sun-sin, a Korean admiral victorious in many naval battles
- Wu Yi, Vice Premier of China
- Yi people, an ethnic group in China
- Yi Jianlian , Chinese NBA basketball player
- Yi language
- Yi script
- Yi, ancient people who lived east of China, see Dongyi
- Yi (Cyrillic) (Ї, ї), a letter of the Ukrainian alphabet
- Yi (drinkware), the ancient Chinese drinkware.
- Yi River, a river in Uruguay
- Lee (Korean name)
- Serbia and Montenegro (FIPS country code YI)
- Yiddish language (ISO 639 language code yi)
- Yi royal family, or Joseon Dynasty of Korea
- Yi, an abbreviation for the IEEE prefix yobi which represents 280.
- An abbreviation for Super Mario World 2: Yoshi's Island, and it's sequel, Yoshi's Island DS
- Hou Yi, a heroic figure from Chinese mythology.
- Yi (editor), a text editor written in Haskell
