This article is a list about the mayors of Longueuil, Quebec and the municipalities that were folded into Longueuil to make the current city.
Before 1961, seven separate communities existed to form what is today known as Longueuil. They merged over the following decades, and Longueuil reached its current state.
This section lists a series of mergers involving Longueuil. In italic is the surviving municipality.
On January 28, 1961, these communities merged, keeping Longueuil's namesake:
In 1969, Longueuil merged again with another neighbouring city:
In October, 1971, neighbouring Saint-Hubert had a merger as well:
On January 1, 2002, Longueuil and seven other south shore municipalities merged:
On January 1, 2006, four of the municipalities previously merged in 2002 voted to secede from Longueuil:
Therefore, Longueuil is currently composed of: