| Brunnisach | |
| Mouth Coordinates: | 47.6679°N 9.4099°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Germany |
| Subdivision Type2: | State |
| Subdivision Name2: | Baden-Württemberg |
| Length: | 15.3km (09.5miles) |
The Brunnisach is a river in Baden-Württemberg, Germany. It flows into Lake Constance, which is drained by the Rhine, near Friedrichshafen.