Juan José Cañas (c. 1826 – January 19, 1918) is perhaps most famous for the (allegedly joint) writing of Himno Nacional De El Salvador (national hymn of El Salvador) with Italian-born composer Juan Aberle.
For much of his early life, Cañas did not live in El Salvador, but instead studied medicine at universities in Nicaragua and Guatemala, before moving back to El Salvador only briefly, going on to work in San Francisco in 1848, to make use of his medical doctrine.
Later in life, Cañas served as diplomatic ambassador to Chile for El Salvador. His poetry can be found at the Central American Poetic Gallery in the Salvadoran Garland.