The Leader of the Official Opposition is one of the keynote speakers at a political conference where the theme is taxes, public spending and growth.
Mulcair will lay out the NDP's vision for what role government can play in promoting growth.
French Prime Minister Manuel Valls will also be in attendance.
The NDP leader also has plans to meet with key leaders of France's Socialist party and government caucus while in Paris.
Mulcair holds dual citizenship from Canada and France and his wife, Catherine Pinhas, was born in France.
The trip comes on the heels of a handful of international trips by Prime Minister Stephen Harper, where the government was able to push its economic and trade agenda around the world.