Garreg Lwyd can refer to any of the following:
- Garreg Lwyd, a hill in the Black Mountain of South Wales which overlies the village of Brynamman in Carmarthenshire
- Garreg Lwyd, a hill near Rhayader in Mid Wales
- Garreg Lwyd, a small estate on the outskirts of Gwyddelwern, North Wales.
Garreg Lwyd is of the Welsh language and translates as 'Grey Stone'