Douglas Aarniokoski (born August 25, 1965) is an American television director and producer.

He is known for his work on the CBS series Star Trek: Discovery, Star Trek: Short Treks, Star Trek: Picard, Criminal Minds, S.W.A.T., and the CW superhero drama Arrow. He has also worked on the FOX supernatural series Sleepy Hollow.

Aarniokoski began his career as a production assistant on the film Turner & Hooch and as Tom Cruise's personal assistant on his 1990 film Days of Thunder. He then worked on the 1992 horror film Dr. Mordrid as first assistant director. He subsequently served as assistant director on several other films, such as From Dusk till Dawn, Living Out Loud, The Faculty, and Spy Kids.

He later began working as second unit director on such films as The Medallion, Once Upon a Time in Mexico, and Resident Evil: Degeneration.