Barryscourt Castle, 15th-century tower house in Carrigtwohill, Ireland.

Barryscourt Castle is a medieval tower house in Carrigtwohill, County Cork, Ireland, built around a central keep with three corner towers and a walled courtyard. The stone structure stands largely intact and gives a clear picture of how a fortified noble residence was arranged.

The site held a wooden watermill in the 7th century, long before any fortification. Barryscourt passed to the Anglo-Norman de Barry family in the 12th century, and the present tower house was probably built around 1550, late in the Barrymore line's tenure. In 1556 it passed to James FitzRichard of the Barryroes. The Barrys backed the Desmond Rebellions of 1569 and 1579 and in 1581 damaged the castle to keep it from Sir Walter Raleigh's forces; after pardon by Elizabeth I it was repaired with a bawn and three corner towers. It ceased as the main residence in 1617 and was captured in 1645.

The name comes from the de Barry family, Anglo-Norman settlers who held the site from the 12th century; the powerful Barrymore branch (Barra mór, "Great Barry") kept it until 1556, when it passed to James FitzRichard of the Barryroes (Barra rua, "Red Barry"). The tower house interior is furnished as it would have been in the 16th century, and guided tours run daily.

The castle is managed by the Office of Public Works and entry is free. There is a car park on site and accessible toilets, so a visit is straightforward for most people.

Cannonball marks from a 1645 attack during the Irish Confederate War are still visible on the outer walls. They are one of the few physical traces of that conflict that can be seen directly on a standing building in the area.