Jean-Louis Fage (30 September 1883, in Limoges – 1964, in Dijon) was a French marine biologist and arachnologist.
A native of Limoges, he studied biology at the Sorbonne and in the laboratory at Saint-Vaast-la-Hougue.
In 1906 he obtained his doctorate with a thesis on the nephridia of polychaetes.
For the next fourteen years he served as a naturalist at the Laboratoire de biologie marine in Banyuls-sur-Mer.