– Patrick Wilson as Daniel Dreiberg / Nite Owl
: A retired vigilante superhero with technological experience.
– Jackie Earle Haley as Walter Kovacs / Rorschach: A superhero who continues his vigilante activities after they are outlawed. He was transformed over time from a “soft” costumed hero into a killer who sees the world in black and white.
– Malin Akerman as Laurie Juspeczyk / Silk Spectre: A retired vigilante superheroine. Akerman described her character as the psychology and the emotion of the film due to being the only woman among the men.
– Billy Crudup as Dr. Jon Osterman / Doctor Manhattan: A superhero with genuine powers who works for the U.S. government.
– Matthew Goode as Adrian Veidt / Ozymandias: A retired vigilante superhero who has since made his identity public.
– Jeffrey Dean Morgan as Edward Blake / The Comedian: A vigilante superhero who is commissioned by the U.S. government.
– Stephen McHattie as Hollis Mason: The first vigilante to take up the mantle of Nite Owl.
– Carla Gugino as Sally Jupiter: A retired vigilante superheroine, mother of Laurie Juspeczyk and the first Silk Spectre.
– Matt Frewer as Edgar Jacobi / Moloch the Mystic: An elderly rehabilitated criminal, known when he was younger as an underworld kingpin and magician.
– Niall Matter as Mothman: He is not a main focus of the storyline, but appears in flashbacks, at one point reduced in his later years to fragile sanity, unnerving the second Silk Spectre. He is regarded fondly by most of the Minutemen, and the first Nite Owl sends the second to visit him, uncostumed, on his behalf.
– Dan Payne as Dollar Bill: A first-generation crimefighter who caught his cape in a revolving door during a bank robbery and was shot to death.
– Danny Woodburn as “The Big Figure”: A dwarf crime boss whom Rorschach put in prison.