Jean Ignace Isidore Gérard (13 September 1803, Nancy, Meurthe-et-Moselle – 17 March 1847, Vanves), generally known by the pseudonym of Jean-Jacques or J. J. Grandville, was a French caricaturist.
He was born at Nancy, in northeastern France, to an artistic and theatrical family. The name "Grandville" was his grandparents' professional stage name. Grandville received his first instruction in drawing from his father, a painter of miniatures. At the age of twenty-one he moved to Paris, and soon afterwards published a collection of lithographs entitled Les Tribulations de la petite proprieté. He followed this with Les Plaisirs de tout âge and La Sibylle des salons (1827); but the work which first established his fame was Les Métamorphoses du jour (1828–29), a series of seventy scenes in which individuals with the bodies of men and faces of animals are made to play a human comedy. These drawings are remarkable for the extraordinary skill with which human characteristics are represented in animal facial features.
Grandville's "metamorphoses" were highly influential to fantastic illustrations. Scènes de la vie privée et publique des animaux used as tarot card.