The Castle of Jadraque (Spanish: Castillo de Jadraque) is a castle in the municipality of Jadraque, Castile-La Mancha, Spain. It sits on a hill commanding the plain of the Henares river. It is sometimes called "Castle of Cid" as it is mentioned in the poem Cantar del Mio Cid.[1]

Built in ashlar stone, it has a rectangular shape with a perimeter of 240 metres. It has four round and one rectangular tower.

Archaeological investigations proved that the site was used since prehistoric times; later it was a fortification of the emirate of Spain and its Moorish descendants. In 1085 it was conquered by the Christians under Alfonso VI of Castile. In 1469 it was bought by cardinal Pedro González de Mendoza.