| Maddox Branch | |
| Source1 Location: | 38.9289°N -77.0942°W |
| Mouth Location: | 38.9189°N -77.1028°W Potomac River |
| Subdivision Type1: | Country |
| Subdivision Type2: | Region |
| Subdivision Name2: | Washington, DC |
| Mouth Elevation: | 7feet |
Maddox Branch is a tributary stream of the Potomac River in Washington, D.C., USA. The historic headwaters of the stream originate in the Tenleytown area in Northwest Washington. The stream flows from the campus of American University south about 1 mile (1.6 km) through Battery Kemble Park, under the Chesapeake and Ohio Canal to the Potomac.