Owen Baker

Liam Aiken

Mrs. Baker

Molly Shannon

Mr. Baker

Kevin Nealon

Hubble (voice)

Matthew Broderick

Wilson (voice)

Donald Faison

Connie Flemming

Brittany Moldowan

Mr. Leone

George Touliatos

Fred

Mikhael Speidel

The Greater Dane's Henchman (voice)

Cheech Marin

Ms. Ryan

Patti Allan

Nelly (voice)

Brittany Murphy

Frankie

Hunter Elliott

Barbara Ann (voice)

Delta Burke

The Greater Dane (voice)

Vanessa Redgrave

Shep (voice)

Carl Reiner

Jo Champa

Mr. Fleming

D. Harlan Cutshall

Wilson's Dad (as Benjamin Ratner)

Ben Immanuel

Bob the Dog Catcher (as Paul C. Vogt)

Paul Vogt

Wilson's Other Dad

Peter Flemming

Mrs. Fleming (as Brenda M. Crichlow)

Brenda Crichlow

Woman at the Pound

Chaka White

Woman at the Pound

Nicola Anderson

TV Anchorman

Ted Friend

House Bidder

Susan Bain

Barbara Ann

Banner

Asian Dad (uncredited)

Mig Macario