| Type: | Ortsteil |
| Municipality: | Petersberg |
| Ostrau | |
| Image Coa: | Wappen Ostrau (Saalekreis).png |
| Coordinates: | 51.6167°N 12.0097°W |
| State: | Sachsen-Anhalt |
| District: | Saalekreis |
| Elevation: | 85 |
| Area: | 17.27 |
| Population: | 1260 |
| Stand: | 2006-12-31 |
| Postal Code: | 06193 |
| Area Code: | 034600 |
Ostrau (pronounced as /de/) is a village and a former municipality in the district Saalekreis, in Saxony-Anhalt, Germany. On 1 January 2010, it merged into the municipality of Petersberg.