The church, located in the small square of the same name in Quartu, was built in 1728-29 thanks to the testamentary bequest of Maria Piras. The building has a late 17th-century style and simplicity of lines. Made of sandstone and unfired earth bricks, it has a rectangular plan with side elevations supported by oblique buttresses, corresponding to the stiffening arches of the interior vault. The facade is simple, with a two-light bell gable, a square doorway, and an oculus.
The interior consists of a single nave with a barrel vault and three round arches. There are two side chapels and a chancel with an octagonal dome. The connection between the nave and chancel is made through a round triumphal arch. The buttresses house two chapels added later. Furnishings include a 1717 bell, a 19th-century pulpit, and a sculptural group depicting St. Bonaventure and the confraternity of St. Ephisius. There are also small wooden statues and Rococo niches with statues of patron saints.
