Portneuf is a municipality in the Portneuf Regional County Municipality, in the province of Quebec, Canada. It is located on the Saint Lawrence River, between Quebec City and Trois-Rivières. The Portneuf River runs on the east side of the town centre.The town of Portneuf is named after a seignory that was founded in 1636, and first settled in 1640.The municipal territory consists of 2 non-contiguous areas, separated by the municipality of Sainte-Christine-d'Auvergne.