Didier Casten studied illustration and comic art at the Institut Saint-Luc in Brussels during the period 1985-88. There, he met fellow artists Paul Burton, Benoît Feroumont and Denis Maghin, and took courses by Jean-Yves Stanicel and others. But it was through Pierre Seron that he entered the comics field.
Starting in 1988, Casten worked with François Walthéry on such projects as 'La Convention des Droits de l'Enfant' (Lombard, 1990) and 'Le Vieux Bleu'. He also contributed to Spirou and cooperated on the animated film 'Le Chameau Blanc'. Casten has done illustration work for Marsu Productions with characters like 'Gaston Lagaffe' and 'Le Marsupilami'. In 1995, he worked with Walthéry again, this time on 'Tchantchès, Gamin des Rues'. He is the author of 'Les Tribulations de Pol' for Info Revue.