Tarzan the Untamed is a book by American writer Edgar Rice Burroughs, the seventh in his series of twenty-four books about the title character Tarzan. It was originally published as two separate stories serialized in different pulp magazines; "Tarzan the Untamed" in Redbook from March to August, 1919, and "Tarzan and the Valley of Luna" in All-Story Weekly from March to April 1920. The two stories were combined under the title of the first in the first book edition, published in 1920 by A. C. McClurg. In order of writing, the book follows Jungle Tales of Tarzan, a collection of short stories about the ape-man's youth. Chronologically, it follows Tarzan and the Jewels of Opar.

Edgar Rice Burroughs was an American writer, best known for his prolific output in the adventure, science fiction, and fantasy genres. Best known for creating the characters Tarzan and John Carter, he also wrote the Pellucidar series, the Amtor series, and the Caspak trilogy.