| Type: | Stadt |
| Gronau | |
| Image Coa: | Wappen Gronau (Leine).png |
| Coordinates: | 52.0667°N 56°W |
| Image Plan: | Gronau (Leine) in HI.svg |
| State: | Niedersachsen |
| District: | Hildesheim |
| Samtgemeinde: | Leinebergland |
| Elevation: | 79 |
| Area: | 88.13 |
| Postal Code: | 31028 |
| Mayor: | Karl Heinz Gieseler SPD |
| Licence: | HI |
| Gemeindeschlüssel: | 03254043 |
| Website: | www.gronau-leine.de |
Gronau (pronounced as /de/) is a town and a municipality in the district of Hildesheim, in Lower Saxony, Germany. It is situated on the River Leine, approximately 15 km southwest of Hildesheim, and 35 km south of Hanover. Since 1 November 2016, the former municipalities Banteln, Betheln, Brüggen, Despetal and Rheden are part of the municipality Gronau.
Gronau is also the seat of the Samtgemeinde ("collective municipality") of Leinebergland.
Honiton, United Kingdom, is twinned with Gronau.