Cousin of the Bernheim-Jeune family, Hessel worked in their art dealing firm before becoming an independent dealer. From c. 1912 he represented Vuillard, for whom Hessel's wife, Lucie, was a frequent subject. In 1932 Hessel was named Officier de la Legion d'Honneur.
Bernard, Tristan. "Jos Hessel," La Renaissance 13 (January 1930):2-5.