Dunamase or the Rock of Dunamase is a rocky outcrop in County Laois, Ireland. Rising 46 metres (151 ft) above a plain, it has the ruins of Dunamase Castle, a defensive stronghold dating from the early Hiberno-Norman period with a view across to the Slieve Bloom Mountains. It is near the N80 road between the towns of Portlaoise and Stradbally.