Église Saint-Symphorien d'Illkirch-Graffenstaden, Catholic church in Illkirch-Graffenstaden, France.

Saint-Symphorien is a Neo-Romanesque basilica-plan church oriented to the east, with a main nave, two side aisles, a lower recessed choir and a twin-tower facade to the west. The facade's three niches hold sculptures of Christ flanked by Saint Symphorian and Saint Catherine of Alexandria, beneath a small rose window. The nave has seven bays; the towers, raised to 42 metres in 1890, carry slate spires and clock faces.

In 1859 the growing population of Illkirch made the old church too small, and the Karlsruhe architect Heinrich Hübsch was commissioned to design a replacement. The church was built in Neo-Romanesque style from 1863 to 1865 on land provided by the Fux-Koessler family. The towers were originally low, with pyramid roofs barely rising above the nave ridge; they were raised to their present 42-metre height and given pointed spires in 1890.

The church is one of three Catholic places of worship in Illkirch-Graffenstaden and belongs to the Communauté des Paroisses catholiques St Florent, in the Strasbourg pastoral zone of the Archdiocese of Strasbourg. Its patron saint, Symphorianus, is shown in a niche above the entrance, flanked by Saint Catherine of Alexandria and Christ; the three bells were cast by the Edel foundry and paid for by the Fux couple.

The church stands at the western end of Avenue Messmer, close to the town centre of Illkirch-Graffenstaden. The main entrance is the arched portal in the twin-tower west facade; the nave is entered from there. The building is listed in the Base Mérimée, and its exterior was repainted in 2007.

The Fux couple, who had provided the building plot, also paid for the church's three bells, cast by the Edel foundry, and for three windows in the choir. The 1866 organ by Stiehr and Mockers originally had 33 stops on two manuals and pedal; Gaston Kern overhauled it in 1975 and added an eight-stop Rückpositiv.