Juan Fernández (c. 1536 – c. 1604) was a Spanish explorer and navigator in the Pacific regions of the Viceroyalty of Peru and Captaincy General of Chile west of colonial South America. He is best known for the discovery of a fast maritime route from Callao (Peru) to Valparaíso (Chile) as well as for the discovery of the Juan Fernández Islands off the coast of Chile.