| Glonn | |
| Mouth Coordinates: | 47.8536°N 12.017°W |
| Subdivision Type1: | Country |
| Subdivision Name1: | Germany |
| Subdivision Type2: | State |
| Subdivision Name2: | Bavaria |
| Length: | 28.7km (17.8miles) |
| Basin Size: | 145km2 |
Glonn is a river in Bavaria, Germany.
Its source is in Glonn in the Ebersberg district and it flows in the south-east direction via Beyharting (Tuntenhausen) to Bad Aibling, where it flows into the Mangfall.
The Glonn has a length of about . Its name originates from "Glana", "the clear one" (female) in Celtic languages.