Mary Deros is a municipal politician in Montreal, Quebec, Canada. She has represented Parc-Extension on Montreal city council since 1998. Deros serves on the Montreal executive committee in Michael Applebaum's administration with responsibility for cultural communities. She was previously an executive committee member in the administrations of Pierre Bourque and Gérald Tremblay. Originally elected as a member of Vision Montreal, Deros subsequently joined Union Montreal before becoming an independent councillor in December 2012; in June 2013, she reaffiliated with the new Équipe Denis Coderre.