Loch Leven Castle is a ruined castle on an island in Loch Leven, in the Perth and Kinross local authority area of Scotland. Possibly built around 1300, the castle was the site of military action during the Wars of Scottish Independence. In the latter part of the 14th century, the castle was granted to William Douglas, 1st Earl of Douglas, by his uncle. It remained in the Douglases' hands for the next 300 years. Mary, Queen of Scots, was imprisoned there in 1567–68, and forced to abdicate as queen, before escaping with the help of her gaoler's family. In 1588, the queen's gaoler inherited the title of Earl of Morton, and moved away from the castle. In 1675, Sir William Bruce, an architect, bought the castle and used it as a focal point for his garden; it was never again used as a residence.
Today, the remains of the castle are protected as a scheduled monument in the care of Historic Environment Scotland. Loch Leven Castle is open to the public in summer, and access is available by ferry.