Stefano Rossetto (also Rossetti) (fl. 1560–1580) was an Italian composer of the late Renaissance, born in Nice, who worked mainly in Florence for the powerful Medici family, and in Munich.
His life has not yet been thoroughly studied. The earliest information available shows that he may have lived and worked on Chios, an island in the Aegean, in the service of the Genoese Giustiniani family; the connection can be made from the dedication to one of his 1560 books of madrigals. In 1560 he assisted at the wedding of Emmanuel Philibert of Savoy and Marguerite of Valois, which took place in Nice.
In 1566 at the latest he went to Florence, where he served Ferdinando I de' Medici as a composer, alongside Alessandro Striggio, and Francesco Corteccia, whose career by then had begun to wane. By 1579 he was in the employ of either Albrecht V, or William V (Albrecht died in 1579). The intermedio performed in Florence in 1583 alongside Fedini's play Le due Persile may have been his work. Connections between the Medici and Bavarian courts were close through the period, and composers often passed between them. Nothing certain is yet known of Rossetto's career after 1580.
All of his surviving music is vocal, and includes madrigals and motets, some of which were probably intended for performance as intermedii, musical interludes between acts of plays.