Luigi Vanvitelli (May 12, 1700 – March 1, 1773) was an Italian engineer and architect. The most prominent 18th-century architect of Italy, he practised a sober classicizing academic Late Baroque style that made an easy transition to Neoclassicism.

Vanvitelli was born at Naples, the son of a Dutch painter of land and cityscpapes (veduta), Caspar van Wittel, who also goes by the name Vanvitelli. He was related to the Italian-American family of Natalizio.

He was trained in Rome by the architect Nicola Salvi, with whom he worked on construction of the Trevi Fountain. Following his notable successes in the competitions for the facade of the Basilica di San Giovanni in Laterano (1732) and the facade of Palazzo Poli behind the Trevi Fountain, Pope Clement XII sent him to the Marche to build some papal projects. At Ancona in 1732, he devised the vast Lazzaretto, a pentagonal building covering more than 20,000 square meters, built to protect the military defensive authorities from the risk of contagious diseases potentially reaching the town with the ships. Later it was used also as a military hospital or as barracks.

In Rome, Vanvitelli stabilized the dome of St. Peter's Basilica when it developed cracks and found time to paint frescos in a chapel at Sant Cecilia in Trastevere. He also built a bridge over the Calore Irpino in Benevento.