Otis Adelbert Kline (1891–1946) was an American adventure novelist, songwriter, and literary agent. His fiction appeared frequently in Weird Tales, where he wrote fantasy and adventure stories for pulp readers. Kline was also interested in Arabic language and culture, and studied Arabic as an amateur.

He was a friend and sometime collaborator of writer E. Hoffmann Price. Kline’s work is associated with the exotic adventure fiction popular in the pulp era, as well as with the business of representing writers.