Saint Mary's Tower (Maltese: Torri ta' Santa Marija), also known as the Comino Tower (Maltese: Torri ta' Kemmuna), is a large bastioned watchtower on the island of Comino in Malta.

[2] Funds for its construction were raised primarily by means of the sale of Comino brushwood,[3] and the total cost was 18,628 scudi, 5 tari and 10 grani, which made it the most expensive of all the Wignacourt towers.

[5] The tower is a large, square building with four corner turrets, and is located about 80 metres above sea level.

Knights who were convicted of minor crimes were occasionally sentenced to the lonely and dangerous task of manning St. Mary's Tower.

In 1799, the insurgents transferred the tower's cannons to blockade batteries to bombard French positions.

For several decades it was deemed to be property of the local civil authorities, and may have been used as an isolation hospital, or even as a wintering pen for farm animals.

It served as a lookout and staging post to guard against contraband and the illegal hunting of migratory birds at sea.