Eddie Murphy as Dr. John Dolittle

Ossie Davis as Archer Dolittle

Oliver Platt as Dr. Mark Weller

Peter Boyle as Calloway

Richard Schiff as Dr. Gene Reiss

Kristen Wilson as Lisa

Jeffrey Tambor as Dr. Fish

Kyla Pratt as Maya

Raven-Symoné as Charisse

Steven Gilborn as Dr. Litvack

Erik Dellums as Jeremy

June Christopher as Diane

Cherie Franklin as Mrs. Parkus

Norm Macdonald as Lucky (voice)

Chris Rock as Rodney (voice)

Albert Brooks as Tiger (voice)

Jenna Elfman as Owl (Voice)

Reni Santoni as Rat #1 (Voice)

John Leguizamo as Rat #2 (Voice)

Julie Kavner as Female Pigeon (voice)

Garry Shandling as Male Pigeon (voice)

Ellen DeGeneres as Prologue Dog (voice)

Paul Reubens as Raccoon (voice)

Eddie Frierson as Skunk (voice)

Phil Proctor as Drunk Monkey (Voice)

Gilbert Gottfried as Compulsive Dog (Voice)

Brian Doyle-Murray as Old Beagle (voice)

Doug Shamburger as Pound Dog (voice)

Jeff Doucette as Possum (voice)

Archie Hahn as Heavy Woman's Dog (voice)

Tom Towles as German Shepherd (voice)

Royce D. Applegate as 'I Love You' Dog (voice)

Chad Einbinder as Bettleheim the Cat (voice)

Jonathan Lipnicki as Baby Tiger (voice)

Hamilton Camp as Pig (voice)

Kerrigan Mahan as Penguin (voice)

Mark Adair-Rios as Intern

Don Calfa as Patient at Hammersmith

Kellye Nakahara as Beagle Woman

Beth Grant as Woman

Yule Caise as Vet's Assistant

Charles Branklyn as Security Guard

Richard Penn as Mr. Galvin

Karl T. Wright as Reporter

Stan Sellers as Cop #1

Ming Lo as Cop #2

Paul Giamatti as Blaine (uncredited)

Benny Buettner as Circus Clown (uncredited)

Pruitt Taylor Vince as Patient at Hammersmith (uncredited)

Crystal the Monkey as Drunk Monkey (uncredited)

Kellan Patrick as Jumping Boy (uncredited)

Kay Yamamoto as Receptionist

Brian Kwan as Busboy

L. Peter Callender as Policeman

Arnold F. Turner as Animal Control Officer

Raymond Matthew Mason as 3-Year-Old John Dolittle

John Lafayette as Reverend

Phyllis Katz as Goat (voice)

Dari Gerard Smith as 5-Year-Old John Dolittle

Bebe Conrad as Circus Clown (uncredited)

Cliff McLaughlin as Mounted Policeman

James F. Dean as Orangutan (voice)

Spencer Kayden as Circus Audience (uncredited)