Petitot studied at the Académie Royale d'Architecture where he won the prestigious Prix du Rome. He studied for four years in Rome and subsequently was appointed in 1753 Architetto delle Fabbriche Ducali at Parma. There he remained for the rest of his extremely active life, building a great deal and establishing, in 1757, an architectural academy that was extremely influential in setting the pattern and standards for the future development of architecture in northern Italy.