The Rotonda di San Lorenzo is a church located in the main square of the city of Mantua in Northern Italy. It was constructed during the late 11th century during the reign of the powerful Canossa family.

The church is a fine example of Romanesque architecture, with a central plan and Byzantine-style frescoes. It's primarily composed of bricks, according to the Lombard tradition, but also includes marble detailing. After construction, the church was dedicated to the martyr St. Lawrence. 

The Rotonda has undergone many transformations and was deconsecrated in 1579. During the following centuries, it was utilized as a warehouse and after the roof was removed, it became a private courtyard for the Jewish quarter of the city.

During the early half of the 20th century, the former church was covered by other buildings, and in 1908 it was rediscovered. The dome was officially reconstructed in 1926. After external additions were removed and the building was restored, the church was once again consecrated and reopened to the public.