Originally from Montreal, Justice Dominique Bélanger studied at Collège Regina Assumpta, École Henri-Bourassa Classique and Collège Marie-Victorin. A graduate of Université de Montréal's Faculty of Law (LL.L. 1979), she was called to the Quebec Bar in 1980, and then completed her studies in law by obtaining a master's in commercial law in 1981. Having begun her career in private practice at Chicoine et associés in Varennes, she later joined the law firm Stikeman Elliott, in Montreal, where she specialized in civil and commercial litigation. In 1986, she joined Quebec City's Legal Department, and then moved to Kronström Desjardins. In 1991, she founded her own law firm, Pâquet Bélanger. Throughout her practice, Justice Bélanger taught for over ten years at the Quebec Bar School. For nearly twenty years, she taught at the Quebec Bar's annual Intensive Trial Advocacy Seminar. She also held several positions within the Young Bar Association of Montreal, the Young Bar Association of Quebec City, and the Quebec City Bar.
She was appointed as a member of the Administrative Tribunal of Québec in 1998, where she was primarily assigned to the economic affairs division and the territory and environment division. Justice Bélanger was appointed to the Superior Court on April 21, 2005. There she served as the class action coordinator and coordinating judge for the district of Montmagny and, later, the district of Beauce. She was appointed to the Court of Appeal on November 2, 2012, where she has served as the coordinating judge for the Quebec City division and provincial administrator since June 2018.