San Salvatore in Mustolio is a Romanesque- style, Roman Catholic church located on Piazza of the same name in central Lucca, region of Tuscany, Italy.

The exterior facade has some 12th-century reliefs in the architraves: one depicting a Eucharistic meal; the second, a miracle of San Nicolao Prete signed by Biduino.

Inside the church in 1820 was a main altarpiece depicting the Ascension of Christ by Paolo Zacchia il Vecchio.

A canvas of the Assumption of Mary by Bonuccio Trénta, had been moved here from the former church of San Pietro Maggiore.

There was also a St Jerome by Alessandro Ardente of Faenza, and a Saints Zita and Paolino by Gaspare Mannucci.