Saint-Pourçain-sur-Sioule (French pronunciation: [sɛ̃ puʁsɛ̃ syʁ sjul], literally Saint-Pourçain on Sioule; Auvergnat: Sant Porçanh de Siula) is a commune in the Allier department in Auvergne-Rhône-Alpes in central France.

[3] It is named after Saint Pourçain, a 6th century AD freed slave who was founder of a local monastery.

The commune is located 28 km (17 mi) north of Vichy and 32 km (20 mi) south of Moulins on the former Route nationale 9 (departmental road 2009).

The river Bouble forms part of the commune's southern border, then flows into the Sioule, which flows north-northeast through the commune and crosses the town.

Two prevention plans of natural risks have been prescribed on the basins of the "Sioule" and of the "Allier", and have both been approved respectively in year 1999 and 2008.