| Lesum | |
| Subdivision Type1: | Country |
| Subdivision Name1: | Germany |
| Subdivision Type2: | State |
| Subdivision Name2: | Bremen |
| Subdivision Type5: | City |
| Subdivision Name5: | Bremen |
| Length: | 9.85km (06.12miles) |
| Source1 Location: | Confluence of the Wümme and Hamme rivers near Ritterhude |
| Source1 Coordinates: | 53.1714°N 8.7425°W |
| Source1 Elevation: | 4m (13feet) |
| Mouth: | Weser |
| Mouth Location: | Bremen-Vegesack |
| Mouth Coordinates: | 53.1667°N 8.6244°W |
| Mouth Elevation: | 4m (13feet) |
| Basin Size: | 2187km2 |
| Tributaries Left: | Wümme |
| Tributaries Right: | Hamme |
The Lesum is a 9.85km (06.12miles) river in northern Germany, right tributary of the Weser, navigable for Class III ships.[1] It is formed at the confluence of the rivers Wümme and Hamme, near Ritterhude, northwest of Bremen. It flows west and flows into the Weser in Bremen-Vegesack.