 | Laura Linney als Dr. Karen Ross |
 | Dylan Walsh als Dr. Peter Elliot |
 | Ernie Hudson als Captain Munro Kelly |
 | Tim Curry als Herkermer Homolka |
 | Grant Heslov als Richard |
 | Adewale Akinnuoye-Agbaje als Kahega |
 | Joe Don Baker als R.B. Travis |
 | Lorene Noh als Amy |
 | Mary Ellen Trainor als Moira |
 | Misty Rosas als Amy the Gorilla |
 | Stuart Pankin als Boyd |
 | Carolyn Seymour als Eleanor Romy |
 | Romy Rosemont als Assistant |
 | James Karen als College President / Elliot's Boss |
 | Bill Pugin als William |
 | Lawrence T. Wrentz als Prof. Arliss Wender |
 | John Hawkes als Bob Driscoll |
 | Bruce Campbell als Charles Travis |
 | Jimmy Buffett als 727 Pilot |
 | Thom Barry als Samahani |
 | Karara Muhoro als Roadblock Soldier |
 | Kevin Grevioux als Roadblock Officer |
 | Taylor Nichols als Jeffrey Weems |
 | Joel Weiss als TraviCom Operator |
 | Robert Almodovar als Rudy, TraviCom Security |
 | Peter Jason als Mr. Janus |
 | Delroy Lindo als Captain Wanta |
 | Joe Pantoliano als Eddie Ventro |
 | Kathleen Connors als Sally |
 | James Paradise als Transport Worker #1 |
| William John Murphy als Transport Worker #2 |
| Ayo Adejugbe als African Airport Guard |
| Darnell Suttles als Hospital Interrogator |
| Michael Chinyamurindi als Claude from Mombasa |
| Willie Amakye als Lead Porter |
| Malang als Porter |
| Jay Speed Forney als Porter |
| Shelton Mack als Porter |
| David Mungai als Porter |
| Anthony Mutune als Porter |
| Sylvester Mwangi als Porter |
| Les Robinson als Porter |
| Nelson Shalita als Porter |
 | E.J. Callahan als DC-3 Pilot |
| Guy Toley als DC-3 Co-Pilot |
| Jackson Gitonga als Mizumu Tribesman |
| Andrew Kamuyu als Mizumu Tribesman |
| Fidel Bateke als Witch Doctor |
| Shayna Fox als Amy (voice) |
| David Anthony als Gorilla |
| Brian La Rosa als Gorilla |
 | John Munro Cameron als Gorilla (as John Cameron) |
| John Alexander Lowe als Gorilla |
 | Jay Caputo als Gorilla |
| Garon Michael als Gorilla |
 | Peter Elliott als Gorilla |
 | David St. Pierre als Gorilla |
| Eldon Jackson als Gorilla |
 | Philip Tan als Gorilla |
 | Nicholas Kadi als Gorilla |
| Christopher 'Critter' Antonucci als Gorilla |
| Frank Marshall | Executive Producer |
| Frank Marshall | Director |
| Anne V. Coates | Editor |
| John Patrick Shanley | Screenplay |
| Jerry Goldsmith | Original Music Composer |
| Allen Daviau | Director of Photography |
| Michael Crichton | Author |
| Kathleen Kennedy | Producer |
| Sam Mercer | Producer |
| Kevin Dean | Rigging Grip |
| Paul Pav | Location Manager |
| Scott Farrar | Visual Effects Supervisor |
| Donna Cline | Production Illustrator |
| Taylor Black | Set Dressing Artist |
| Tove Blue Valentine | Cableman |
| Laurie Gonzales | Craft Service |
| Terrence Harris | Casting Associate |
| Hector C. Gika | Foley Editor |
| Alexander Courage | Orchestrator |
| Doug Hemphill | Sound Re-Recording Mixer |
| Richard Holland | Supervising Art Director |
| Carol Kiefer | Art Department Coordinator |
| Daniel B. Ossello | Special Effects Coordinator |
| Gregg Baxter | Supervising Sound Editor |
| Paul C. Babin | Camera Operator |
| M. James Arnett | Stunt Coordinator |
| Dave Robling | Transportation Coordinator |
| Mike Milliken | Color Timer |
| William S. Maxwell III | Leadman |
| Jerry Moss | Property Master |
| David Daunt | Camera Technician |
| Stephen S. Campanelli | Steadicam Operator |
| Sashy Bogdanovich | Set Production Assistant |
| Kevin Arnold | Lighting Coordinator |
| Chris Napolitano | Rigging Gaffer |
| Michael Backes | Associate Producer |
| Gary A. Beaird | Grip |
| Cynthia Barr | Makeup Artist |
| Bruce Richter | Carpenter |
| Chris 'Kid' Schwartz | Post Production Assistant |
| Tom Marshall | Transportation Captain |
| Rick Bozeat | Sound Effects Editor |
| Michael McGovern | Visual Effects Editor |
| Frank Yablans | Executive Producer |
| Merrick Morton | Still Photographer |
| Kathleen Jo Stude-Elliott | Post Production Supervisor |
| Ron Judkins | Sound Mixer |
| John Giuliano | Propmaker |
| Darrell Hall | Music Editor |
| Tina Gonzalez | Visual Effects Coordinator |
| Allison Cowitt | Casting |
| J. Michael Riva | Production Design |
| Marilyn Matthews | Costume Design |
| Tom Lifsey | Construction Foreman |
| Jeff Frost | Sculptor |
| Cheryl Beasley Blackwell | Costume Supervisor |
| Christina Smith | Key Makeup Artist |
| Lydia Bottegoni | Visual Effects Producer |
| Charlie Daboub | Set Designer |
| Tom Connole | Additional Photography |
| Angela Heald | Production Supervisor |
| Susan Schuler-Page | Hairstylist |
| Anne Marie Stein | Unit Publicist |
| Andy Birmingham | Production Accountant |
| Robert Jackson | Boom Operator |
| Michael P. Cook | Dialogue Editor |
| Paul Deason | Associate Producer |
| Wendy Riva | Assistant Art Director |
| Scott Fair | Driver |
| Katterli Frauenfelder | First Assistant Director |
| James Thatcher | Musician |
| Terry Scott | Construction Coordinator |
| John French | Painter |
| Judith A. Cory | Key Hair Stylist |
| Faith Conroy | Script Supervisor |
| Michael Denering | Scenic Artist |
| Paul Deason | Unit Production Manager |
| Claudia Mullaly | Visual Effects Art Director |
| Mike Fenton | Casting |
| Lisa Fischer | Set Decoration |
| Chris Cowan | Mechanical Designer |
| Eric Sundahl | Art Department Assistant |
| Seth Arnett | Stunts |
| Dana Arnold | Lighting Technician |
| Tara Meaney-Crocitto | Production Coordinator |
| Desmond Cannon | Assistant Sound Editor |
| Michael Lantieri | Special Effects Supervisor |
| Dan Perri | Title Designer |
| Laura Nisbet Peters | Second Second Assistant Director |
| Robert Batha | First Assistant Sound Editor |
| Sherman Labby | Storyboard Artist |
| Randy Singer | Foley Mixer |
| Mark Cotone | Second Assistant Director |
| Lesley Neufeld | Textile Artist |
| Bob Baron | ADR Mixer |
| Lissa Ruben | Continuity |
| Mary C. Lane | Costumer |
| Laura Graham | ADR Editor |
| M. James Arnett | Second Unit Director |
| Craig Raiche | Assistant Property Master |
| Tom Southwell | Concept Artist |
| Ken Dufva | Foley Artist |
| Renee Napier | Contact Lens Technician |
| Nerses Gezalyan | Foley Recordist |
| Nigel Holland | Sound Effects Designer |
| Richard L. Carden | Dolly Grip |
| Bobby Huber | First Company Grip |
| Saul Saladow | Visual Effects Assistant Editor |
| Keith Woulard | Stunt Double |
| Louis Niemeyer | Assistant Camera |
| Pamela Bentkowski | Foley Supervisor |
| Craig Tex Barnett | Special Effects Technician |
| John Gazdik | Visual Effects Camera |
| Elyse Couvillion | Second Assistant Camera |
| Larry Wallace | Chief Lighting Technician |
| William R. Mayberry | Assistant Chief Lighting Technician |
| Tim Wooster | Focus Puller |
| Deborah Roth | Researcher |
| Rachel Davies | Casting Assistant |
| Adam Shankman | Choreographer |
| Belinda Celis | Production Secretary |
| Jerry Goldsmith | Conductor |
| Deborah J. Page | Assistant Location Manager |
| J.W. 'Corkey' Fornof | Aerial Coordinator |
| Cary Shott | Assistant Editor |
| Carlos Cordero | Local Casting |
| Jenny Pont | Location Coordinator |
| Stiles White | Production Assistant |
| Sean T. Stratton | Post Production Coordinator |
| Jules Sylvester | Animal Coordinator |
| Patrick R. Siembieda | Assistant Accountant |
| Rusty Reilly | Second Company Grip |
| Doug Jones | Negative Cutter |
| Dorne Huebler | Digital Compositor |
| Werner Keppler | Special Effects |
| Kenneth Chamitoff | Extras Casting |
| Chuck Picerni Jr. | Stunts |
| Peter McAdams | Best Boy Grip |
| Gilbert B. Combs | Stunts |
| Brian Smrz | Stunts |
| Lisa McCullough | Stunts |
