| Muddy Branch | |
|---|---|
 Muddy Branch Stream near Esworthy Rd | |
 | |
| Location | |
| Country | United States |
| State | Maryland |
| Counties | Montgomery |
| Physical characteristics | |
| Source | |
| • location | Gaithersburg, MD |
| Mouth | Potomac River |
• location | North of Pennyfield Lock, Potomac, MD |
• coordinates | 39°03′16″N 77°17′37″W / 39.05444°N 77.29361°W |
| Length | 11.9 miles (19.2 km) |
Muddy Branch is a tributary stream of the Potomac River in Montgomery County, Maryland, United States, located about 14 miles (23 km) northwest of Washington, D.C.