Jean-François Guay studied the saxophone at McGill University, the National Regional Conservatory in Bordeaux, France, and Université Laval. His main teachers were Jean-Marie Londeix, Rémi Ménard, and Abe Kestenberg.

Jean-François Guay is a respected performer and educator. He has enriched the saxophone repertoire through collaborations with renowned composers such as Christian Lauba, François Rossé, Éric Champagne, Denis Dion, Robert Lemay, Bruce Mather, Laurie Radford, and Alain Perron. He has premiered many new works, both as a soloist and as a member of various ensembles. He has recorded five albums with Fidelio, Oratorio, and SNE, all of which have received excellent reviews from Canadian media.

He is a member of the Nelligan Saxophone Quartet, with which he has performed in numerous concerts and recordings. He specializes in contemporary music, with many pieces for saxophone dedicated to him, though he also plays classical music.

Jean-François Guay teaches saxophone at Cégep Marie-Victorin and Université de Montréal. Additionally, he is the founder and a professor of the international saxophone workshop at Cégep Marie-Victorin, alongside Jean-Michel Goury, a professor at the Boulogne-Billancourt Conservatory in France. He was also the founding president of the Association des saxophonistes du Québec.