| Image Coa: | DEU Ellerau COA.svg |
| Coordinates: | 53.7575°N 9.9158°W |
| Image Plan: | Ellerau in SE.svg |
| State: | Schleswig-Holstein |
| District: | Segeberg |
| Elevation: | 24 |
| Area: | 7.09 |
| Postal Code: | 25479 |
| Area Code: | 04106 |
| Licence: | SE |
| Gemeindeschlüssel: | 01 0 60 019 |
| Website: | www.ellerau.de |
| Mayor: | Ralf Martens |
Ellerau is a municipality in the Kreis (district) of Segeberg in Schleswig-Holstein, north Germany. It is situated some 24 km north of Hamburg, and 8 km northwest of Norderstedt.