Juan Fernández Pacheco y Téllez Girón (1419 in Belmonte – 1 October 1474 in Trujillo), was a Castilian noble of Portuguese descent who rose to power in the last years of the reign of Juan II of Castile and came to dominate the government of Castile during the reign of his son and successor Henry IV of Castile. His titles included, among others, Marquess of Villena, Duke of Escalona and Master of the Order of Santiago.