Ormacleit Castle (also Ormiclate or Ormaclett) is a ruined mansion house of the early 18th century. It is located on South Uist in the Western Isles of Scotland. It was built in the early years of the 18th century by Allan Macdonald, chief of Clanranald, and occupied from 1707. Macdonald was killed at the Battle of Sheriffmuir on 13 November 1715, and Ormacleit Castle is said to have burned down on the same day.