Jean-Baptiste Madou was a Belgian painter and lithographer.

Madou was born in Brussels. He studied at the Brussels Academy of Fine Arts and was a pupil of Pierre Joseph Célestin François. While draftsman to the topographical military division at Kortrijk, he received a commission for lithographic work from a Brussels publisher. It was about 1820 that he began his artistic career. Between 1825 and 1827 he contributed to Les Vues pittoresques de la Belgique, to a Life of Napoleon, and to works on the costumes of the Netherlands, and later made a great reputation by his work in La Physionomie de la société en Europe depuis 1400 jusqu'à nos jours (1836) and Les Scenes de la vie des peintres.

It was not until about 1840 that Madou began to paint in oils, and the success of his early efforts in this medium resulted in a long series of pictures representing scenes of village and city life, including The Fiddler, The Jewel Merchant, The Police Court, The Drunkard, The Ill-regulated Household, and The Village Politicians. Among his numerous works mention may also be made of The Feast at the Chateau (1851), The Unwelcome Guests (1852, Brussels Gallery), generally regarded as his masterpiece, The Rat Hunt (acquired by Leopold II, king of the Belgians), The Arquebusier (1860), and The Stirrup Cup. At the age of sixty-eight he decorated a hall in his house with a series of large paintings representing scenes from La Fontaine's fables, and ten years later made for King Leopold a series of decorative paintings for the Château de Ciergnon. Madou died in Saint-Josse-ten-Noode on 31 March 1877 and was buried in the local cemetery.

He created the Société Royale Belge des Aquarellistes.