Louis Roule ([lwi ʁul]; 20 December 1861 – 30 July 1942) was a French zoologist born in Marseille.
In 1910 he succeeded Léon Vaillant (1834–1914) as chair of zoology (reptiles and fish) at the Muséum national d'histoire naturelle in Paris, a position he would hold until 1937.
During this time period he was also an instructor at the Institut National Agronomique (from 1925), and director of the laboratory of ichthyology at the École pratique des hautes études (EPHE).
He analyzed collections gathered from Prince Albert I of Monaco, as well as specimens obtained from the Antarctic expeditions of Jean-Baptiste Charcot (1867–1936).
He had an avid interest in the work of French naturalists of previous generations, publishing books on Buffon, Daubenton, Lamarck and Cuvier.