Marguerite-D'Youville (French pronunciation: [maʁɡəʁit djuvil]) is a regional county municipality located in the Montérégie region of southwestern Quebec, Canada.

The RCM was formerly named Lajemmerais Regional County Municipality, after Christophe du Frost de Lajemmerais, the father of Marguerite d'Youville.

On February 12, 2011, the name was changed to honour d'Youville directly.

[4] Since the 2016 census, the name has correctly been displayed as "Marguerite-D'Youville."

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