Craigend Castle is a ruined country house, located to the north of Milngavie, in East Dunbartonshire, central Scotland.
The lands of Craigend were part of the Barony of Mugdock in medieval times, but the estate was sold in the mid-17th century to the Smith family. John Smith (1724–1812) was born at Craigend and became a merchant and the founder, in 1751, of booksellers John Smith & Son. John Smith built a plain house on the estate, but after his death his son, James Smith, incorporated that house in a much more ornate mansion. It was designed by Alexander Ramsay, in what is described as Regency Gothic style.
Glasgow businessman William Wilson and his son opened a zoo at Craigend in 1949 with various exotic animals but it failed to attract significant visitors and closed in 1954.
The grounds became part of Mugdock Country Park and the house has become a ruin. The stable block, located to the north of the house, now serves as the country park visitor centre.