Philippe Viannay (15 August 1917 - 27 November 1986) was a French journalist.
He founded the Centre de formation des journalistes, and, later, the sailing school Les Glénans.
During World War II, he led a resistance movement named Défense de la France. They printed an underground journal which distributed up to 400,000 copies.
The Canadian journalist Caitlin Kelly—who studied with Viannay at the Centre in Paris on an eighth-month journalism fellowship—later described him as "the most inspiring man I've ever met."
During the first year of the German occupation, Viannay married the former Hélène Mordkovitch. Hélène Viannay co-administered Les Glénans with her husband, and following Viannay's death became president of the association of Ancient Résistants of Défense de la France.
The French Fondation de la Résistance awards an annual prize for resistance-era histories, the Prix Philippe Viannay-Défense de la France.