Pierre-De Saurel (French pronunciation: [pjɛʁ də soʁɛl]) is a regional county municipality in the Montérégie region in southwestern Quebec, Canada.

Originally named Le Bas-Richelieu Regional County Municipality, the name change to Pierre-De Saurel took effect on January 1, 2009.

It is located on the Richelieu River, downstream from La Vallée-du-Richelieu Regional County Municipality at the confluence of the Richelieu and Saint Lawrence River.

The RCM is named after Pierre de Saurel, a captain of the Carignan-Salières Regiment who rebuilt Fort Richelieu in 1666 and later became the area's seigneur.

Highways and numbered routes that run through the municipality, including external routes that start or finish at the county border:[9]