Kirby Castle or Kirby Muxloe Castle is a ruined, fortified manor house in Leicestershire, England.
Work on the castle was begun in 1480 by William, Lord Hastings on the site of a pre-existing manor house. Work continued quickly until 1483, when William was executed during Richard, Duke of Gloucester’s, seizure of the throne. The castle then remaining largely incomplete.
After a short period of inhabitation, Kirby Castle fell into ruin during the course of the 17th century. In 1912, the Commissioners of Work repaired the brickwork and carried out an archaeological survey.
Today, the castle is controlled by English Heritage and open to visitors.