After studying art humanities at the Saint-Luc Institute in Liège and spending some time in Mittéï’s and Seron’s workshops, Marc Hardy began his career at Spirou with episodes of Histoires de l'Oncle Paul in 1971 and in Le Journal de Tintin in 1974 with an episode of Modeste et Pompon (written by Mittéï) and two of Marc Franval (written by Édouard Aidans).
After 1974 he only worked for Spirou, creating Badminton with Mittéï and, the next year, Garonne et Guitare, which he would draw until 1978 from scripts by Mythic.
His classic but loose style makes him a prolific creator of short stories and covers.
In 1984, he launched Arkel with writer Stephen Desberg and, most notably, Pierre Tombal with Raoul Cauvin—a series that brought him success and financial security: as of 2012, it numbered 28 volumes.
He abandoned Arkel in 1986 to focus his young public production exclusively on Pierre Tombal.
Also in 1984, he began a collaboration with Yann on more adult series.
The duo published three volumes of La Patrouille des libellules (pre-published in Circus from 1984-87), six of Lolo et Sucette (1989-2001), and two of Croqu'la vie (1992-94).
The year 2005 saw the publication by Dargaud of the first volume of Feux, created with writer Philippe Tome.