The Chronicle star will take on the role in the sequel to The Amazing Spider-Man.
Director Marc Webb confirmed the casting news in a tweet on Monday (03Dec12), writing, "Meet Harry Osborn. @danedehaan" and attaching a photo of the actor.
Franco played Osborn/The Green Goblin in Sam Raimi's Spider-Man trilogy, opposite Tobey Maguire. Dehaan will star alongside Andrew Garfield. Shailene Woodley will also appear in the latest Spider-Man sequel as Mary Jane Watson and Jamie Foxx has been cast as the villainous Electro.