In 1687, after his conversion to Catholicism, Magnol eventually became 'Demonstrator of plants' at the botanic garden of Montpellier. In 1693, recommended by Guy-Crescent Fagon (1638–1718), then court physician, and his own student Joseph Pitton de Tournefort (1656–1708), he was nominated 'doctor to the kings court'. In 1694 he finally was appointed Professor of medicine at the University of Montpellier. Through intervention of Fagon, he received a "brevet de professeur royale". Magnol was also appointed Director of the botanic garden in 1696, for a three-year period. After that, he received the title 'Inspector of the garden' for the rest of his life.