 | Eddie Murphy als Dr. John Dolittle |
 | Kristen Wilson als Lisa Dolittle |
 | Kyla Pratt als Maya Dolittle |
 | Raven-Symoné als Charisse Dolittle |
 | Steve Zahn als Archie (voice) |
 | Lisa Kudrow als Ava (voice) |
 | James Avery als Eldon |
 | Andy Richter als Eugene Wilson |
 | Lil' Zane als Eric |
 | Denise Dowse als Secretary |
 | Elayn J. Taylor als Eldon's Wife |
 | Kevin Pollak als Riley / Alligator |
 | Victor Raider-Wexler als Judge B. Duff |
 | Jeffrey Jones als Joe Potter |
 | Mark Griffin als Logger / Nature Show Narrator |
 | Ken Hudson Campbell als Animal Control Officer / Dog / Animal Groupie #3 / Forest Animal (voice) |
 | Anne Stedman als Woman |
 | Tommy Bush als Farmer |
 | Adam Vernier als Farm Worker |
 | Chris Marley als Yuppie Man |
 | Shaun Robinson als Newscaster |
 | Googy Gress als Bear Announcer |
| Lisa Marie Hugueley als Shamu Trainer |
 | Steve Irwin als The Crocodile Hunter |
| Doug Seus als Klondike Dave Delivery Man |
| Louise Osbourne als Waitress |
| Brie Hill Arbaugh als Chihuahua Lady |
| E.J. Wessel als Guy Throwing Frisbee |
 | Jacob Vargas als Pepito (voice) |
 | Michael Rapaport als Joey the Raccoon (Voice) |
 | Isaac Hayes als Possum (voice) |
 | Andy Dick als Lennie the Weasel (voice) |
 | Joey Lauren Adams als Squirrel (voice) |
| Maria Arcé als Fish (voice) |
| Melique Berger als Fish (voice) |
 | David Cross als Dog / Animal Groupie #2 (voice) |
 | David DeLuise als School Fish #2 (voice) |
| Trevor Denman als Horse Race Announcer (voice) |
 | John DiMaggio als Seeing Eye Dog / Wassup Fish / Mouse (voice) |
 | Georgia Engel als Giraffe (voice) |
 | Mike Epps als Sonny (voice) |
 | Jamie Kennedy als Bandit / Forest Animal / Animal Groupie #1 (voice) |
 | Tom Kenny als Male Tortoise (voice) |
 | Clyde Kusatsu als Bee (voice) |
 | Cedric the Entertainer als Zoo Bear #1 (voice) |
 | David L. Lander als Bird (voice) |
 | Michael McKean als Bird (voice) |
 | Tara Mercurio als Deer (voice) |
 | Mandy Moore als Girl Bear Cub |
 | Frankie Muniz als Boy Bear Cub (voice) |
 | Bob Odenkirk als Animal Groupie #4 / Forest Animal / Dog (voice) |
 | Phil Proctor als Drunk Monkey (voice) |
 | Reni Santoni als Rat #2 (voice) |
 | Richard C. Sarafian als God Beaver (voice) |
 | Hal Sparks als School Fish #1 (voice) |
 | Renée Taylor als Female Tortoise (voice) |
 | John Witherspoon als Zoo Bear #2 (voice) |
 | Keone Young als Bee (voice) |
 | Jodi Essex als Frisbee Thrower in Park (uncredited) |
 | Lawrence Pressman als Governor of California (uncredited) |
 | Norm Macdonald als Lucky (voice) |
 | Crystal the Monkey als Drunk Monkey (uncredited) |
 | Bart the Bear II als Boy Bear Cub |
 | Arnold Schwarzenegger als White Wolf (voice) (archive sound) (uncredited) |
| Larry Levin | Screenplay |
| John Davis | Producer |
| Joseph Singer | Producer |
| Daryn Okada | Director of Photography |
| Craig Herring | Editor |
| Steve Carr | Director |
| David Newman | Original Music Composer |
| Camille Friend | Hairstylist |
| Michele Imperato Stabile | Co-Producer |
| Neil A. Machlis | Executive Producer |
| Aldric La'Auli Porter | Associate Producer |
| Heidi Santelli | Co-Producer |
| Juel Bestrop | Casting |
| Jeanne McCarthy | Casting |
| William Sandell | Production Design |
| Brad Ricker | Art Direction |
| Bruce Crone | Supervising Art Director |
| Robert Gould | Set Decoration |
| Ruth E. Carter | Costume Design |
| Michele Imperato Stabile | Unit Production Manager |
| Patricia Klawonn | Set Designer |
| Bill Taliaferro | Set Designer |
| Diana Jaher | Casting Associate |
| Nadia Lubbe Simon | Casting Assistant |
| Iddo Lampton Enochs Jr. | Location Manager |
| Jasan Sherman | Location Scout |
| Craig W. van Gundy | Location Manager |
| Nancy Karlin | Script Supervisor |
| Kris Fullan Martinez | Production Coordinator |
| Hugh Lofting | Creator |
| Kris Evans | Makeup Department Head |
| Erma Kent | Hair Department Head |
| Judy Murdock | Makeup Artist |
| Aldric La'Auli Porter | First Assistant Director |
| Joe A. Hawthorne | Painter |
| Gerald Lehtola | Art Department Coordinator |
| Bryan McBrien | Greensman |
| Robert McDonald | Propmaker |
| Frank McEldowney | Greensman |
| Thomas Meikle | Sculptor |
| Robert Prchal | Propmaker |
| Hugo Santiago | Set Designer |
| Hal Schlax | Propmaker |
| Mark Wade | Property Master |
| Butch West | Construction Coordinator |
| Ted Caplan | Dialogue Editor |
| Zack Davis | ADR Editor |
| R.J. Kizer | Dialogue Editor |
| Dave Kulczycki | Sound Effects Editor |
| Vanessa Lapato | ADR Editor |
| Harrison D. Marsh | Boom Operator |
| Donald Sylvester | Supervising Sound Editor |
| Dan Yale | Foley Editor |
| Alan E. Lorimer | Special Effects Coordinator |
| Peter S. Elliot | Visual Effects Editor |
| Mitchell Ferm | Visual Effects Coordinator |
| John Kilkenny | Visual Effects Producer |
| Liz Radley | CG Supervisor |
| Douglas Smith | Visual Effects Supervisor |
| John Molo | Stunt Coordinator |
| Todd Dos Reis | Camera Operator |
| Jason D. Hodges | Dolly Grip |
| Mike Hodges | Key Grip |
| Casey Hotchkiss | Camera Operator |
| Kal Manning | Gaffer |
| Bruce McBroom | Still Photographer |
| Larry McCarron | Dolly Grip |
| Craig Anthony | Key Costumer |
| Donna Marcione Pollack | Costume Supervisor |
| Elizabeth Frank | Set Costumer |
| Spring Aspers | Music Supervisor |
| Jim Harrison | Music Editor |
| Kim Strand | Music Editor |
| Tom Villano | Music Editor |
| Hugh Lofting | Story |
| Evan Gilner | Additional Second Assistant Director |
| David Hyman | Second Assistant Director |
| Michelene Mundo | Second Second Assistant Director |
| Amy Schmidt | Second Assistant Director |
| Douglas Smith | Second Unit Director |
| Sharon Swab | Second Second Assistant Director |
| Mark Tobey | First Assistant Director |
| Tina Fortenberry | Production Supervisor |
| Daniel M. Stillman | Unit Production Manager |
| Rich Thorne | Second Unit Director |
| George Randell | Best Boy Grip |
| Kirk A. Holland | Transportation Captain |
