Catherine Fournier (French pronunciation: [katʁin fuʁnje]; born 7 April 1992) is a Canadian politician, who was elected as mayor of Longueuil on November 7, 2021.

She was previously member of the National Assembly of Quebec, having been elected in a by-election on December 5, 2016 at the age of 24.

She holds an economics major and political science minor from the Université de Montréal.

[2] In 2023, Fournier revealed she had been the victim of sexual assault by Harold Lebel, a former Quebec MNA.

The assault took place during the evening of October 20, 2017, while Fournier and Lebel, who were PQ MNAs at that time, were in Rimouski to introduce their party's plan to combat poverty.