He was a 17th-century Venetian librettist and opera impresario, best remembered for his close collaboration with the composer Francesco Cavalli. He was active as an impresario at the Teatro San Cassiano (the first public opera house, opened in 1637), the Teatro San Moisè (founded in 1639), and the Teatro Sant’Apollinare, which he rented together with business partners from 1650 for his own opera productions.

Faustini wrote 14 libretti, the majority of which were set to music by Cavalli—eleven of them specifically for him—while a few were later used by other composers. Some libretti left incomplete at his death were finished by his brother Marco Faustini, who continued his work as an impresario and successfully managed several theatres in Venice.

Together with Cavalli, Faustini formed the most successful composer-librettist partnership in Venice during the 1640s. Following the death of Monteverdi, this period saw the emergence of opera in its modern sense, alongside a rapid expansion of public opera houses in the city. Faustini played a central role in this transformation, helping to shift opera from courtly entertainment or private performances to a commercial and public art form. This evolution was reflected in his libretti, which incorporated elements of contemporary popular literature and the Commedia dell’arte.

Shortly after the premiere of La Calisto at the end of 1651, for which he wrote the libretto, Faustini died. Shortly before his death, he had opened the Teatro Sant’Apollinare.