Rossi was born in Genoa, where he studied with his uncle, Lelio Rossi (1601-1638), at the Cathedral of San Lorenzo. Around the year 1624 he moved to Rome to enter the service of Cardinal Maurizio of Savoy. It was there that he met the madrigal composer Sigismondo d'India as well as the keyboard composer Girolamo Frescobaldi, with whom he may have studied. Rossi's two books of madrigals, which have only recently come to scholarly attention, were likely written during this period. Rossi's madrigal output from this period is remarkably chromatic, to a level mached only by the music of such experimental composers as Carlo Gesualdo. The circumstances of Rossi's dismissal from the Cardinal's service in 1629 are unclear.
Rossi's first known opera dates from his second period of Roman service, while in the retinue of the wealthy Taddeo Barberini. His opera Erminia sul Giordano was premiered during the Carnival of 1633 at the theatre of the Palazzo Barberini (Rossi himself apparently sang on stage as the sun-god Apollo), and appeared in print four years later. A second opera, Andromeda (1638, partly lost) was first performed in Ferrara in 1638. By 1649, Rossi had returned to Rome and was residing in the palace of Camillo Pamphili (a relative of Pope Innocent X), perhaps in semi-retirement. He died in Rome in July 1656 and may have been buried in the church of Sant'Andrea delle Fratte.
Although Rossi was famed as an outstanding violinist in his lifetime, today his reputation rests chiefly on his keyboard music. In particular his 10 Toccatas are highly regarded (amongst these, Toccata VII with its wildly chromatic ending is best known). They are stylistically close to the music of Girolamo Frescobaldi, Carlo Gesualdo and Johann Jakob Froberger, while being individual, and they enjoy a reputation as a significant milestone in the keyboard literature.
- Rossi, Michelangelo The Madrigals of Michelangelo Rossi. Edited by Brian Mann. 240 p., 6 halftones, 7 musical examples, 1 table. 9 x 12 2002 Series: (MRM) Monuments of Renaissance Music ISBN 978-0-226-50338-7 (ISBN 0-226-50338-0), 2003