| Image Coa: | DEU Groß Grönau COA.svg |
| Coordinates: | 53.8003°N 10.7539°W |
| Image Plan: | Groß Grönau in RZ.svg |
| State: | Schleswig-Holstein |
| District: | Herzogtum Lauenburg |
| Amt: | Lauenburgische Seen |
| Elevation: | 7 |
| Area: | 4.9 |
| Postal Code: | 23627 |
| Area Code: | 04509 |
| Licence: | RZ |
| Gemeindeschlüssel: | 01 0 53 041 |
| Website: | www.amt- lauenburgische- seen.de |
| Mayor: | Hans Georg Weißkichel |
| Party: | CDU |
Groß Grönau is a municipality in the district of Lauenburg, in Schleswig-Holstein, Germany.