The two worked together 25 years ago on Batman Returns. Burton directed the film and Keaton starred as the superhero himself.
Keaton would assume the role of the evil circus owner who exploits Dumbo, the adorable little elephant.
Will Smith recently passed on a role in the film. He was asked to play the children who befriend Dumbo's father.
Transformers' Ehren Kruger wrote Dumbo's script.
Danny DeVito plays the circus' ringmaster. Colin Farrell is also in talks to join the film.