Sinds de film officieel op 15 oktober van start mocht gaan, is de casting in gang gezet. Martin Freeman (The Hitchhikers Guide to the Galaxy) speelt Bilbo Baggins, de held van het verhaal. Richard Armitage (tv-serie MI-5) speelt Thorin Oakenshield, de leider van een groep dwergen die het gaat opnemen teven een draak.
Peter Jackson over de casting: "Despite the various rumors and speculation surrounding this role, there has only ever been one Bilbo Baggins for us. There are a few times in your career when you come across an actor who you know was born to play a role, but that was the case as soon as I met Martin. He is intelligent, funny, surprising and brave - exactly like Bilbo and I feel incredibly proud to be able to announce that he is our Hobbit." En hij vervolgt: "Richard is one of the most exciting and dynamic actors working on screen today and we know he is going to make an amazing Thorin Oakensheild. We cannot wait to start this adventure with him and feel very lucky that one of the most beloved characters in Middle-earth is in such good hands."
Over de reeds aanwezige geruchten dat Aidan Turner (Being Human van tv) en Rob Kazinsky (EastEnders, ook van tv) de rollen spelen van Kili en Fili, zegt Jackson: "Rob is an extremely talented young actor with a huge career in front of him, I'm thrilled that he has agreed to take on the role of Fili. Besides his talent as an actor, Rob is also a champion sword fighter; I'm looking forward to seeing the damage he can do to a horde of marauding Goblins!Adian is a wonderfully gifted young actor who hails from Ireland. I'm sure he will bring enormous heart and humor to the role of Kili."
Graham McTavish (Secretariat) speelt de dwerg Dwalin; John Callen dwerg Oin; Stephen Hunter dwerg Bombur, Mark Hadlow dwerg Dori en Peter Hambleton speelt dwerg Gloin.
Jackson medlt ook nog: "Graham is a terrific actor, with a great depth of experience, which I know he will bring to the role of "Dwalin. I have worked with Mark Hadlow on many projects; he is a fantastic actor. I am thrilled to be working with both of them on these movies. I am also proud to announce the casting of New Zealand actors as Peter Hambleton, John Callen and Stephen Hunter. Fran and I know that they will bring great depth and talent to our Company of Dwarves."
De twee delen van The Hobbit draaien in december 2012 en december 2013 in de bioscoop. Hieronder een aantal acteurs die zijn gecast, met van links naar rechts Richard Armitage, Mark Hadlow, Stephen Hunter, Rob Kazinsky, Graham McTavish en Aidan Turner: