As a young man he served as an intern at the Hôpital du Midi as an understudy to Philippe Ricord (1800–1889).

In 1863 he became médecine des hôpitaux, and from 1867 worked with Augustin Grisolle (1811–1869) at the Hôtel-Dieu de Paris.

[1] His main contribution to medical science was the study of congenital syphilis, of which he provided a description of in 1883.

In addition, in 1901 he founded an organization devoted to spreading knowledge to combat syphilis, called the Société Française de Prophylaxie Sanitaire et Morale.

[1] His name is associated with the following three medical terms: Along with his study of venereal disease, Fournier was also a medical historian, republishing works by erstwhile physicians that included Girolamo Fracastoro (1478–1553), Giovanni de Vigo (1460–1525) and Jacques de Béthencourt.