Jean Marie Visconti , in Italian Giovanni Maria Visconti , is a noble Italian born in Italy in 1388 and dead the May 16th 1412 in Milan. It was the 2nd duke of Milan in 1402.

He was the son of Jean Galéas Visconti and Catherine Visconti, itself girl of Barnabé Visconti. He had as a brother Philippe Marie who succeeded to him. He was hardly thirteen years old with died of his father and his/her mother assumed the regency of her duchy. In little time, the duchy disintegrated. In the middle of the confrontations between rival factions, carried out by captains of fortune and mercenaries, a man without scruples emerged, Facino Cane. This one succeeds, while being based on the sanguinary character of Jean Marie, to instill in him a feeling of suspicion with regard to the regent. Catherine was imprisoned in 1404 with Monza, where she died a little later probably poisoned or perhaps victim of the Peste.

In 1408, it married Antonia, girl of Charles Ier Malatesta, lord of Rimini, and of Elisabeth de Mantoue but they did not have a posterity.

Jean Marie made himself famous for his dogs, mâtins which it had drawn up to devour of the alive men. It is said that, when in May 1409, whereas the city was still in war, the famished people shouted on his passage “Peace! Peace! ”, it unchained on him its army rabble which massacred two hundred personnes  ; following that, it prohibits, under penalty of hanging, that the words peace and war are marked and obliged even the ecclesiastics to say, during the messe : “ gave nobis tranquillitatem ” to the place of pacem .

Some entreated benefitted from the period when Facino Cane, largest Condottiere of the duchy, lay seriously wounded with Pavia to assassinate Jean Marie in front of the church San Gottardo of Milan, the May 16th 1412.

Dying Facino Cane made swear, the very same day, with its officers to support the heir to Jean Marie, Philippe Marie, and he proposed moreover, that his wife, Béatrice of Tightens, wife the new duke after his death, which took place indeed shortly after.