Leonard Helperman / Chihuahuas (39 episodes, 2000-2002)
Mr. Jolly / Congressman / Doberman / Intercom at dog show / Mr.Jolly / Narrator / Narrator on TV / Stomach (38 episodes, 2000-2002)
Pretty Boy (37 episodes, 2000-2002)
Spot Helperman (34 episodes, 2000-2002)
Mrs. Helperman / Mary Lou Helperman / Grandma Rose (34 episodes, 2000-2002)
Ian Wazselewski / Air Show Customer / East-Westland Dog Show announcer / Golden retriever / MacDougal's owner / Male dog owners #1 and #3 / Scottish blue bloodhound / Sheep dog / Unnamed dog (27 episodes, 2000-2002)
Taylor / Trevor / Tyler / Buddy / Teddy Naven / Kelsey / Ruth (21 episodes, 2000-2002)
Leslie Dunkling / Girl #1 / Girl #2 / Girl #3 / Leslie (19 episodes, 2000-2002)
Younghee Mandlebom / Younghee Mandel-Baum / Ruth (19 episodes, 2000-2002)
Principal Strickler / Principal Crosby Strickler (17 episodes, 2000-2002)
Kelsey / Chelsey / Girl in class / Leslie Dunkling (13 episodes, 2000-2002)
Spot Helperman / Scott Leadready II / Scott Leadready II (segment: "Fresh 'n' Frozey Chocolaccino") / Scott Leadready II (segment: "Mr. Jolly: Man... Or Mouser?") / Scott Leadready II (segment: "Team Scott") (8 episodes, 2002)
Amber Lee / Joan of Arc / Kittens / Miss Regina Fabalina Fancypaws / Regina Fabalina (5 episodes, 2000-2001)
Tallulah / Bus Driver / Librarian (4 episodes, 2000-2001)
Electronic litter box / Leroy / Male dog owners #2 and #4 / Myron the Magnifico / TV announcer (4 episodes, 2002)
Steve Kanickee / Astronaut (3 episodes, 2000-2002)
Mr. Wazselewski (3 episodes, 2000-2002)
5th Grade Teacher (2 episodes, 2000)
Mary Beth / Mrs. Dunkling (2 episodes, 2000-2002)
Gary (2 episodes, 2001-2002)
Emma Whitemill (2 episodes, 2001)
Max (2 episodes, 2002)
Principal Nash Brickler (2 episodes, 2002)
Clown / Emilio / Train Conductor (1 episode, 2000)
Spooky (1 episode, 2001)
Fifi (1 episode, 2000)
Students (1 episode, 2000)
Dutch Calenza (1 episode, 2000)
Mr. Naven (1 episode, 2000)
Franklin Delano Roosevelt (1 episode, 2001)
Miss Deweygood (1 episode, 2002)
Fred Bitters (1 episode, 2002)
Fred (1 episode, 2000)
Steve Kanickee (1 episode, 2000)
Additional Voices (1 episode, 2001)
Old man #2 (1 episode, 2001)
Security Guard (1 episode, 2000)
Cosmetics saleswoman (1 episode, 2000)
Cat Shelter Owner (1 episode, 2001)
Mrs. Wazselewski (1 episode, 2000)
Miles (1 episode, 2000)
Narrator / Tim Tim Tim (1 episode, 2000)
Eli (1 episode, 2001)
Fabulous Gelatin Singer / Free Bird (1 episode, 2002)
Granny (1 episode, 2002)
Margarita Ratoncita (1 episode, 2002)
Baseball Coach (1 episode, 2002)
Mr. Poppy Puttinpuss (1 episode, 2002)
Lurkey (1 episode, 2002)
Female customer (1 episode, 2002)
Eric Mark Kravitz (1 episode, 2002)
Umpire (1 episode, 2002)
Miss Sproutwell (1 episode, 2002)
Clancy the Lunch Lady (1 episode, 2002)
Female Customers (1 episode, 2002)
Miles (1 episode, 2002)