Giovanni Valentini (ca. 1582 – 29/30 April 1649) was an Italian Baroque composer, poet and keyboard virtuoso. Overshadowed by his contemporaries, Claudio Monteverdi and Heinrich Schütz, Valentini is practically forgotten today, although he occupied one of the most prestigious musical posts of his time. He is best remembered for his innovative usage of asymmetric meters and the fact that he was Johann Kaspar Kerll's first teacher.