Fernando Rodríguez (or Fernán Ruiz) de Castro (1125–1185) is a Castilian nobleman, statesman and military leader who makes his career in León.
He is the leader of the House of Castro during the civil wars that follow the death of Sancho III of Castile and the succession of the infant Alfonso VIII.
He is nicknamed el Castellano ("the Castilian") in León and el Leonés ("the Leonese") in Castile.