Louis Marie-Auguste Boutan (6 March 1859 – 6 April 1934) was a French biologist and photographer.

The son of Augustin Boutan [fr], he was born in Versailles and studied biology and natural history at the University of Paris.

During that year, with his brother Auguste [fr], he developed equipment for underwater photography.

After the war, he began research into the artificial production of pearls, one of the first people to investigate this subject.

[2] Boutan was named to the International Scuba Diving Hall of Fame as an early pioneer in 2010.