literary theorist, philologist, dramatist, and poet, an important innovator in Italian drama.

Born into a wealthy patrician family in Vicenza, a cultural centre in his time, Trissino traveled widely in Italy, studying Greek in Milan and philosophy in Ferrara and frequenting Niccolò Machiavelli's literary circle in Florence before settling in Rome. There he associated with the humanist Pietro Bembo, became close friends with the dramatist Giovanni Rucellai, and served Popes Leo X and Clement VII.

Trissino's most significant cultural contribution was the Hellenization of Italian drama, achieved almost solely through his masterpiece, the blank-verse tragedy Sofonisba (written 1514–15, published 1524, first performed 1562), based on a story about the Carthaginian wars by the Roman historian Livy and employing the dramatic techniques of Sophocles and Euripides. Sofonisba, though not an interesting drama in itself, incorporated profound innovations in intent, structure, and form. The sources were Greek and devoid of religious or educational purpose; choruses were used to indicate divisions in the action; the unities of time and action were studiously followed; and verso sciolto (“blank verse”) was employed extensively for the first time in Italian drama. Trissino wrote a later verse comedy, I simillimi (published 1548), based on the Roman playwright Plautus' Menaechmi. He also wrote the first Italian odes modeled on the irregular lyric verse of the Greek poet Pindar and the first Italian versions of the Horatian ode. His La poetica (1529) used Italian poetry to exemplify his theory.

Trissino also exerted a formative influence on Andrea di Pietro della Gondola (Palladio, Andrea), whom he discovered working as a mason on his villa. He educated the young man in his academy, gave him the name Palladio, and took him on two visits to Rome that profoundly affected his development into a great architect.