The Teen Wolf star will appear alongside Owen Wilson and Vince Vaughn in the 20th Century Fox comedy, reports Variety.
The Shawn Levy-helmed movie stars Wilson and Vaughn as two old-school salesmen who find themselves unemployed and set adrift in the modern world.
The pair attempt to reinvent themselves by taking on internships at a large and successful tech company.
O'Brien will play a fellow intern at the organisation.
He was mostly recently seen in features The First Time and The High Road.
Shooting on The Internship is scheduled to begin today.