Slieve Commedagh (from Irish Sliabh Coimhéideach, meaning 'the guarding/watching mountain')[4] is a mountain with a height of 767 m (2,516 ft) in County Down, Northern Ireland.

The Mourne Wall passes east–west over the mountaintop, and there is a small tower at the summit.

There are also the remains of an ancient burial cairn on the mountaintop.

[2] Slieve Commedagh overlooks the Glen River to the east, and the Pot of Legawherry to the west.

[2] On its southern side are a group of granite tors known as 'the Castles'.