Jason Momoa undertook an intense six-week training program at a stunt and martial arts academy in Los Angeles for his part while still finalizing negotiations for the film. After putting tremendous effort into the role, he later expressed regret about the mediocre quality of the film. "I've been a part of a lot of things that really sucked, and movies where it's out of your hands," Momoa stated in an interview with GQ magazine. "'Conan was one of them. It's one of the best experiences I had and it [was] taken over and turned into a big pile of shit."
Jason Momoa is by his own admission afraid of horses, so all his horse riding scenes had to either be faked or filmed with doubles.
Dolph Lundgren, then Mickey Rourke, were in talks to play Corin, Conan's father, but Rourke turned it down to do Immortals (2011) before Ron Perlman was cast.
While in pre-production, Conan was a temporary title for the film, until it was changed to Conan 3D. Finally, early in December 2010, the title was changed to Conan the Barbarian, the same as the 1982 film.
Jason Momoa and Rachel Nichols would later be offered the roles of Drax the Destroyer and Gamora in Guardiani della Galassia (2014). Both turned the roles down, and Dave Bautista and Zoe Saldaña, respectively, took them. All four were present for PR tours of projects the same day in 2009, passing The Rose Playhouse /Museum, where that movie would have a large PR day afterward in London, UK.