Giovanni Battista Castello (1500 or 1509–1569 or 1579) was an Italian historical painter. Born in Gandino near Bergamo, he is ordinarily termed Il Bergamasco to distinguish him from the other painter (of miniatures) with the identical name from school of Genoa. His best-known works are the paintings on the vault of the Basilica della Santissima Annunziata del Vastato. He was an architect and sculptor as well as painter. He decorated rooms of the , near Bergamo, with scenes from the Iliad.