| Grey Abbey | |
| Native Name: | An Mhainistir Liath |
| Native Name Lang: | ga |
| Order: | Franciscans |
| Founder: | William de Vesci |
| Established: | 1260 |
| Status: | Inactive |
| Public Access: | Yes |
Grey Abbey is a ruined Franciscan abbey/monastery in County Kildare, Ireland. Founded in 1260, the Kildare poems were likely written in the abbey.
The abbey was founded in 1260 by William de Vesci, however it was completed by Maurice FitzGerald, Lord of Offaly. Gerald FitzGerald, 5th Earl of Kildare was buried here.
A manuscript which is the original source of the Kildare poems was likely written in the Grey Abbey in the early 1300s.