He was a frequent visitor at the Thrales; and his name occurs repeatedly in Boswell's Life. In 1769 he was tried for murder, having had the misfortune to inflict a mortal wound with his fruit knife on a man who had assaulted him on the street. Johnson among others gave evidence in his favour at the trial, which resulted in Baretti's acquittal. He died in May 1789. His first work of any importance was the Italian Library (1757), a useful catalogue of the lives and works of many Italian authors. The Lettere famigliari, giving an account of his travels through Spain, Portugal and France during the years 1761-1765, were well received, and when afterwards published in English (4 vols., 1770), were highly commended by Johnson.
While in Italy on his travels Baretti set on foot a journal of literary criticism, to which he gave the title of Frusta letteraria, the literary scourge. It was published under considerable difficulties and was soon discontinued. Among his other numerous works may be mentioned a useful Dictionary and Grammar of the Italian Language, and a dissertation on Shakespeare and Voltaire. His collected works were published at Milan in 1838.