Michaux was born at Versailles. In 1779 he spent some time botanizing in England, and in 1780 he explored Auvergne, the Pyrenees and the north of Spain. In 1782 he was sent by the French government on a botanical mission to Persia. His journey began unfavourably, as he was robbed by Arabs of all his equipment except his books; but he gained influential support in Persia, having cured the shah of a dangerous illness. After two years he returned to France with a fine herbarium, and also introduced numerous Eastern plants into the botanic gardens of France. In 1785 he was sent by the French government to North America, and travelled with his son Francois André (1770-1855) through Canada, Nova Scotia and the United States. On his return to France in 1797 he was shipwrecked and lost most of his collections. In 1800 he went to Madagascar to investigate the flora of that island, and died there of a tropical fever. His work as a botanist was chiefly done in the field, and be added largely to what was previously known of the botany of the East and of America.
He wrote two valuable works on North American plants: the Histoire des chenes de l'Amerique septentrionale (1801), with 36 plates, and the Flora Boreali-Americana (2 vols., 1803), with 51 plates. His son Francois published a Histoire des arbres forestiers de l'Amerique septentrionale (3 vols., 1810-1813), with 156 plates, of which an English translation appeared in 1817-1819 as The North American Sylva.