Clough Oughter Castle
- Location: Cavan, Ireland
- Country: Ireland
Clough Oughter Castle, Lough Oughter, Co Cavan
Situated near Killeshandra town is the impressive Clough Oughter Castle sited on an island in the middle of Lough Oughter.
Built by the Anglo Normans in the early 13th Century, but it was soon captured by the O’Reilly clan, the Irish rulers of East Breifne.
Owen Roe O’ Neill – leader of the anti English revolt of the 1640’s died here in November 1649.