Lorraine is an affluent off-island suburb of Montreal, in southwestern Quebec, Canada on the north shore of the Rivière des Mille-Îles in the Thérèse-De Blainville Regional County Municipality. There are no industries and only a very limited commercial district (comprising one medical center, one shopping mall, a golf course, a gym, a supermarket and arena); almost all houses are of the detached type. Furthermore, a large portion of the town territory is set aside as wild forest (Forêt du Grand Côteau); some bike/ski trails run through it. The town is divided into two areas, Uptown and Downtown (or Lorraine en haut and Lorraine en bas, colloquially, because the northern area is on higher ground). These two areas are also delimited by Quebec freeway A-640, and are only joined together by the main street (Boulevard de Gaulle) overpass.

Lorraine has earned a reputation for high-end homes with pristine lawns. Due to the heat and humidity of summers in the region, many of these properties have in ground swimming pools in backyards. The town prides itself with completely underground utility networks apart from a small older section of the town (Avenue Fraser, Mey and Bruyeres in particular). The absence of telephone and electric poles contributes to the aesthetic appeal of the municipality.

The town was founded February 4, 1960 and is named for the French region of the same name.

The town is the territory of the Roman Catholic parishal community of Charles-de-Foucault (old parish), part of the (new) Saint-Luc parish of the Terrebonne pastoral region of the Saint-Jérôme diocese. The town is now part of the Thérèse-De Blainville federal electoral district (Marc-Aurèle-Fortin federal electoral district) and Blainville provincial electoral district. It makes district 22 of the Seigneurie-des-Milles-Îles French school board and is part of district 8 of the Sir-Wilfrid-Laurier English school board. Lorraine is also a member of the Montreal Metropolitan Community.

The town has three elementary schools: École Le Carrefour and École Le Tournesol, which are very close to each other but separated by Parc Lorraine, as well as École du Ruisselet.