 | Megan Fox als Jennifer Check |
 | Amanda Seyfried als Anita “Needy” Lesnicky |
 | Johnny Simmons als Chip Dove |
 | Adam Brody als Nikolai Wolf |
 | J.K. Simmons als Mr. Wroblewski |
 | Amy Sedaris als Toni Lesnicky |
 | Kyle Gallner als Colin Gray |
 | Chris Pratt als Roman Duda |
 | Cynthia Stevenson als Mrs. Dove |
 | Sal Cortez als Chas |
| Ryan Levine als Mick |
 | Juan Riedinger als Dirk |
| Colin Askey als Keyboardist |
 | Juno Rinaldi als Officer Warzak |
 | Josh Emerson als Jonas Kozelle |
 | Nicole Leduc als Camille |
| Aman Johal als Ahmet from India |
 | Dan Joffre als Raymundo |
 | Candus Churchill als Nutritionist |
 | Carrie Genzel als Mrs. Check |
| Emma Gallello als Little Jennifer |
 | Megan Charpentier als Little Needy |
 | Jeremy Schuetze als Craig |
 | Valerie Tian als Chastity |
 | Emily Tennant als Gossiping Girl |
 | Karissa Tynes als Other Girl |
 | Eve Harlow als Goth Girl |
| Michael Brock als Goth Boy |
 | Genevieve Buechner als Goth Girl #2 |
 | Adrian Hough als Colin's Dad |
 | Gabrielle Rose als Colin's Mom |
 | Michael Bean als Priest |
 | Bill Fagerbakke als Jonas' Dad |
 | Marilyn Norry als Jonas' Mom |
 | Cut Chemist als DJ at Dance |
| Zoe LaLiberté als Candlelight Vigil Singer |
| Chelsey Smith als Candlelight Vigil Singer |
| Whitney Chow als Candlelight Vigil Singer |
| Michael Orstad als Candlelight Vigil Singer |
| Ronnie Robinson als Orderly |
 | Ed Anders als Orderly |
 | Roxanne Wong als Patient #1 |
| Diane Dutra als Patient #2 |
| Maya Toews als The Creepy Hand |
 | Andrea Baker als (voice) |
| Lisa Breitman als (voice) |
 | Cathy Cavadini als (voice) |
 | Lanei Chapman als (voice) |
 | Vicki Davis als (voice) |
 | Jeff Fischer als (voice) |
 | Aaron Fors als (voice) |
 | Barbara Harris als (voice) |
| Caryn Johnson als (voice) |
 | Jeremy Maxwell als (voice) |
 | David Michie als (voice) |
| Levi Nunez als (voice) |
| Paige Pollack als (voice) |
| David J. Randolph als (voice) |
 | Roger Craig Smith als (voice) |
 | Joel Swetow als (voice) |
| Andreana Weiner als (voice) |
 | Lennon Wynn als (voice) |
 | Diablo Cody als Melody Lane Drinking Woman (uncredited) |
 | Lance Henriksen als Passing Motorist (uncredited) |
| Karyn Kusama | Director |
| Daniel Dubiecki | Producer |
| Mason Novick | Producer |
| Jason Reitman | Producer |
| Diablo Cody | Screenplay |
| Brad Van Arragon | Producer |
| Diablo Cody | Executive Producer |
| Stephen Barton | Original Music Composer |
| Theodore Shapiro | Original Music Composer |
| M. David Mullen | Director of Photography |
| Plummy Tucker | Editor |
| Mindy Marin | Casting |
| Arvinder Greywal | Production Design |
| Katia Stano | Costume Design |
| Randall Poster | Music Supervisor |
| J. Michael Williams | Production Manager |
| Jason Blumenfeld | First Assistant Director |
| Tracey Poirier | Second Assistant Director |
| Paolo G. Venturi | Art Direction |
| Doug Girling | Set Designer |
| Gary Hawes | Third Assistant Director |
| Gordon Piper | Third Assistant Director |
| Christine Wilson | Script Supervisor |
| John Dekker | Gaffer |
| Monica Huppert | Makeup Artist |
| Robert A. Pandini | Hairstylist |
| Sandra Matossi | Production Accountant |
| Daniel Dubiecki | Second Unit Director |
| Scott J. Ateah | Stunt Coordinator |
| Ed Anders | Stunt Coordinator |
| Caroline Field | Stunts |
| Krista Bell | Stunts |
| Nesta Chapman | Stunts |
| Loyd Bateman | Stunts |
| Anthony David Moyer | Stunts |
| Kim Howey | Stunts |
| Dan Redford | Stunts |
| Darryl Scheelar | Stunts |
| Owen Walstrom | Stunts |
| Mike Carpenter | Stunts |
| Steven McMichael | Stunts |
| Joe Doserro | Stunts |
| Garvin Cross | Stunts |
| Laura Lee Connery | Stunts |
| Brad Kelly | Stunts |
| Ryan Ennis | Stunts |
| Byron Brisco | Stunts |
| Leslie McMichael | Stunts |
| Cody Laudan | Stunts |
| Mike Mitchell | Stunts |
| Brad Loree | Stunts |
| Brett Armstrong | Stunts |
| Todd Scott | Stunts |
| Teresa Weston | Assistant Art Director |
| Erin Sinclair | Art Department Coordinator |
| James Forsyth | Extras Casting |
| John Clothier | Camera Operator |
| Karl Herrmann | "B" Camera Operator |
| Doane Gregory | Still Photographer |
| Rob Young | Production Sound Mixer |
| Spencer Louttit | Assistant Property Master |
| Wes Hamby | Assistant Property Master |
| Jason Crosby | Marine Coordinator |
| Joanne Leblanc | Set Decoration |
| Chelsea Yusep | Assistant Set Decoration |
| Kevin Griffin-Park | On Set Dresser |
| Chris Dowell | Post Production Supervisor |
| Bruce Szeles | Post Production Supervisor |
| Sarah Jean Porter | VFX Editor |
| Sarah Jean Porter | First Assistant Editor |
| Dave Askey | Key Grip |
| Ellen Anderson | Assistant Costume Designer |
| Debbie Schreiber | Truck Costumer |
| Meg Schmon | Costume Coordinator |
| Tanya Hudson | First Assistant Makeup Artist |
| Beverly Moncrief | Contact Lens Technician |
| Charmaine Clark | First Assistant Hairstylist |
| Neil Robertson | Location Manager |
| Shane Lennox | Assistant Location Manager |
| Sheryl Rhodes | Production Coordinator |
| Trevor Westerhoff | Production Coordinator |
| Rory Cutler | Special Effects Coordinator |
| John Beatty | Construction Coordinator |
| Debbie Van Dusen | First Assistant Accountant |
| Irene Astle | Payroll Accountant |
| Dana Dubé | Animal Coordinator |
| Gloria Davies | Unit Publicist |
| Dave Liboiron | Transportation Coordinator |
| Perry Robertson | Supervising Sound Editor |
| Scott Sanders | Supervising Sound Editor |
| Barney Cabral | Supervising ADR Editor |
| Richard Dwan Jr. | Sound Editor |
| Hector C. Gika | Sound Editor |
| Trevor Metz | Sound Editor |
| Kevin Zimmerman | First Assistant Sound Editor |
| Nick Neutra | Foley Supervisor |
| Kyle Billingsley | Foley Mixer |
| James Bailey | Foley Artist |
| Cynthia Merrill | Foley Artist |
| Alan Freedman | ADR Mixer |
| Mitch Paulson | Digital Colorist |
| Martha Pike | Digital Intermediate Editor |
| Karl Herrmann | Second Unit Director of Photography |
| Sam Harris | Second Unit First Assistant Director |
| Erik Nordby | Visual Effects Supervisor |
| J. Stanley Johnston | Sound Re-Recording Mixer |
| Christopher Elke | Visual Effects Producer |
