Leine is a river of Thuringia and Lower Saxony, Germany, a tributary to the Aller.
Leine may also refer to:
- Leine (Eine), a river of Saxony-Anhalt, Germany, tributary of the Eine
- Leine (Helme), a river of Saxony-Anhalt, Germany, tributary of the Helme
- Leine, the former German name of the village of Linie, in western Poland