Eleuterio Quintanilla Prieto (24 October 1886 in Gijon, Spain – 18 January 1966 in Bordeaux, France) was an Asturian/Spanish anarchist and freemason, educator and pupil of Francisco Ferrer Guardia. Quintanilla was a central member of the CNT and lived in Spain until the end of the Spanish Civil War, when he went into exile in France where he died.