The son of an engraver, Andrea, Agostino Tofanelli studied with his father and brother Stefano. At the age of twelve, he moved from Lucca to Rome and there he absorbed the neoclassical lesson of Anton Raphael Mengs and taught himself by looking at the works of the Renaissance masters. He attended the Accademia del Nudo and participated with great success in academic competitions, but eventually returned to his hometown in early 1788 due to health problems. Highly acclaimed also for his drawing skills, Agostino collaborated in the creation of numerous volumes of engravings, including one with Ennio Quirino Visconti for the bas-reliefs of the Pio-Clementino Museum (1796) and another for the sculptures of Villa Borghese.
Trained in the shadow of his more famous brother Stefano, with whom he collaborated in the decoration of Villa Mansi in Segromigno, Agostino seems to have been a latecomer to the most up-to-date currents of mature Neoclassicism, starting with those of the painters Vincenzo Camuccini and Gaspare Landi. Introduced to the world of patrons by his own brother, he obtained his first commissions and soon began his brilliant career. Until the early years of the century he enjoyed a good name among prestigious clients as a draughtsman and engraver; in 1807 he was appointed custodian of the Capitoline Museum – a position corresponding to the current position of Superintendent of Fine Arts – which he held until his death. His first important assignments as a painter saw him working in Rome at Palazzo Spada (1808) and in the renovation of the Quirinal Palace apartments (Salon de Musique dell’Imperatrice, 1812). In 1813, he was appointed a member of the Accademia di San Luca, to which he donated ApolloandMarsyas, now kept in the institution’s collections together with a Self-Portrait (c. 1820). This was followed by work on Palazzo Taverna (1810-1814), the Vatican Palaces (1817-1818), and the Quirinal Chapel. Other works are to be found in the Church of San Bonaventura dei Lucchesi (portraits of his brother Stefano Tofanelli, c. 1813, and his son Raffaele Tofanelli, c. 1820; The Archangel Raphael, 1822) and in the sacristy of San Carlo al Corso. In Lucca, where he had previously worked for Elisa Baciocchi (1812), he was also commissioned by Maria Luisa of Bourbon (1818-1820) to paint family portraits and works on biblical themes.