| Image Coa: | DEU Westerau COA.svg |
| Coordinates: | 53.7833°N 39°W |
| Image Plan: | Westerau in OD.svg |
| State: | Schleswig-Holstein |
| District: | Stormarn |
| Amt: | Nordstormarn |
| Elevation: | 13 |
| Area: | 15.38 |
| Postal Code: | 23847 |
| Area Code: | 04539 |
| Licence: | OD |
| Gemeindeschlüssel: | 01 0 62 083 |
| Website: | www.amt-nordstormarn.de |
| Mayor: | Heinrich Blunck |
Westerau is a municipality in the district of Stormarn, in Schleswig-Holstein, Germany.