An Mhainistir Liath | |
 Northwest corner of the ruin | |
| Monastery information | |
|---|---|
| Order | Franciscans |
| Established | 1260 |
| People | |
| Founder(s) | William de Vesci |
| Architecture | |
| Status | Inactive |
| Site | |
| Public access | Yes |
Grey Abbey (Irish: An Mhainistir Liath) is a ruined Franciscan abbey/monastery in County Kildare, Ireland. Founded in 1260, the Kildare poems were likely written in the abbey.