Basilica of Saint-Quentin, Minor basilica in Saint-Quentin, France.

The Basilica of Saint-Quentin is a Gothic church building with an elongated interior layout topped by a square tower and slender spire. The structure displays characteristic Gothic features including arches, columns, and ornamental stonework that runs across its walls and ceiling.

Religious buildings have occupied this site since the 4th century, though the current Gothic structure was constructed between the 12th and 15th centuries. The building suffered severe damage in the 20th century but was later rebuilt, marking its story of destruction and restoration.

The church takes its name from Saint Quentin, a 3rd-century missionary beheaded at the site; his relics drew pilgrims throughout the Middle Ages. In 1228 the relics of Quentin, Victoric of Amiens and Cassian of Auxerre were moved from the crypt to the nave, their heads, hands and arms placed in separate reliquaries behind the high altar. The former crypt was kept as a sacred place.

The nave runs west from the 13th-century apse toward the surviving porch-tower, which serves as the entrance; the planned monumental west facade was never built. The spire reaches 83 metres, making the building the tallest in the Aisne department apart from the Fleury and Landouzy transmitters. The church is a listed monument historique, protected on the 1840 list drawn up at Prosper Mérimée's request.

The nave between the two transepts may stand over a Carolingian crypt with a circular corridor, suggested by limited excavations. The 83-metre spire makes the basilica the tallest building in the Aisne department after the Fleury and Landouzy transmitters.