Östrum is a village in the southern part of the borough of Bad Salzdetfurth in Lower Saxony, Germany. The L 490 state road runs through the village crossing with the L493. Its immediate neighbours are the villages of Breinum to the west and Bodenburg to the south.
Ostrum may refer to:
- Östrum, a village in the southern part of Bad Salzdetfurth in Lower Saxony, Germany
- Ostrum (dragon), a fictional dragon in Dragonaut: The Resonance
- Peter Ostrum (born 1957), American large animal veterinarian and former child actor