Since his 2007 graduation from the Conservatoire d'art dramatique de Montréal, Francois Arnaud has trodden the theatrical boards with Carl Béchard (L'imprésario by Smyrne de Goldoni), Benoît Vermeulen (Tendres totems et croquis cruels by Francis Monty), Amanda Kellock (Scapin the Schemer, an adaptation of the Molière play), Teo Spychalski (L'heure du Lynx by Per Olov Enquist) and Luce Pelletier (Awake and Sing by Clifford Odets). At the Conservatory, he performed under the direction of great talents such as Claude Poissant, Hugo Bélanger and Patricia Nolin.

On television, he performed in Taxi 0-22 by Patrick Huard, in The Double Life of Eleanor Kendall by Richard Roy and also in Yamaska by Michel D'Astous and Anne Boyer. His performance earned him a nomination for a Gémeaux prize in 2010 (Best male lead in a drama series).

In cinema, Francois filmed Les grandes chaleurs, a film by Sophie Lorain written by Michel Marc Bouchard, in which he portrayed the character Yannick alongside actress Marie-Thérèse Fortin. François also played the role of Antonin in J'ai tué ma mere, written and directed by Xavier Dolan, which was a 2009 Cannes Film Festival sensation.

Presently, François is playing the role of Cesar Borgia alongside Jeremy Irons in the acclaimed Showtime series The Borgias, directed by Neil Jordan. He filmed the third season this summer in Budapest, Hungary, but before he crossing the Atlantic, Francois filmed the American feature film, Copperhead, by Ron Maxwell.