Saint-Sulpice is a Roman Catholic church in Paris, on the east side of the Place Saint-Sulpice, in the Luxembourg Quarter of the VIe arrondissement. At 113 metres long, 58 metres in width and 34 metres tall, it is only slightly smaller than Notre-Dame and thus the second largest church in the city. It is dedicated to Sulpitius the Pious. During the 18th century, an elaborate gnomon, the Gnomon of Saint-Sulpice, was constructed in the church.
The present church is the second building on the site, erected over a Romanesque church originally constructed during the 13th century. Additions were made over the centuries, up to 1631. The new building was founded in 1646 by parish priest Jean-Jacques Olier (1608–1657) who had established the Society of Saint-Sulpice, a clerical congregation, and a seminary attached to the church.
Work continued for about 140 years: The church was mostly completed in 1732; the chancel is the work of Christophe Gamard, Louis Le Vau and Daniel Gittard, but the work was completed by Gilles-Marie Oppenord, a student of François Mansart, in 1714-1745.