| Lough Barra | |
| Pushpin Map: | Island of Ireland |
| Pushpin Map Alt: | Lough Barra location in Ireland |
| Pushpin Label Position: | none |
| Pushpin Map Caption: | Location in Ireland |
| Location: | County Donegal |
| Inflow: | River Barra |
| Outflow: | Gweebarra River |
| Catchment: | 19.68km2 |
| Basin Countries: | Ireland |
| Length: | 1.4km (00.9miles) |
| Width: | 0.8km (00.5miles) |
| Area: | 0.63km2 |
| Depth: | 4.4m (14.4feet) |
| Max-Depth: | 11.6m (38.1feet) |
| Elevation: | 90m (300feet) |
Lough Barra is a freshwater lake in the northwest of Ireland. It is located in north County Donegal in the valley along the Gweebarra fault.
Lough Barra is about 30km (20miles) west of Letterkenny, just outside the southwest corner of Glenveagh National Park. It measures about 1.5km (00.9miles) long and 1km (01miles) wide.
Lough Barra is fed mainly by the Barra River entering at its northern end. The lake drains southwards into the Gweebarra River. The lake, like other area lakes, is oligotrophic.
Fish species in Lough Barra include brown trout, salmon and the critically endangered European eel. Lough Barra is part of the Cloghernagore Bog and Glenveagh National Park Special Area of Conservation, which also includes Lough Beagh.