Bingbing Li's entire dialogue was dubbed by Sally Cahill who voiced Ada Wong in the video games (Resident Evil 2 (1998), Resident Evil: The Darkside Chronicles (2009) and Resident Evil 4 (2005)). Although she can speak English, Li Bingbing had a thick accent, which required her to be audio dubbed as a result.
The character Becky was not originally to be hearing-impaired, but after an outstanding audition, the role was given to Aryana Engineer. She was scouted by Paul W.S. Anderson and Milla Jovovich, as they were impressed by her performance in Orphan (2009).
While filming a fight scene with Milla Jovovich, a mishap occurred causing 16 actors to fall off a scaffolding and sent to the hospital. As a result, filming was shutdown for a few days and Jovovich visited some of the actors in the hospital out of respect.
(at around 52 mins) During the car chase with the Zombie Russian army the music playing is called 'Phantom Chase' by tomandandy. This references music from the original Resident Evil (1996) video game, particularly 'Second Floor Mansion'.
The scene between Ada Wong and Alice in the underground office is a re-enactment of the scene in Resident Evil 4 (2005) where Leon S. Kennedy meets with Ada for the first time in the Salazar Family castle bedroom. Wong wears the exact same outfit in both the game and this movie. The film also includes Ada's climbing pistol and her interactive sunglasses from that game.