Arnold Saves Sid

Phillip Van Dyke

Arnold (voice)

Francesca Marie Smith

Helga Pataki (voice)

Jamil Walker Smith

Gerald Johanssen (voice)

Olivia Hack

Rhonda Wellington Lloyd (voice)

Anndi McAfee

Phoebe Heyerdahl (voice)

Dan Castellaneta

Grandpa Phil (voice)

Ben Diskin

Eugene Horowitz (voice)

Christopher Walberg

Stinky Peterson (voice)

Justin Shenkarow

Harold Berman(voice)

Dom Irrera

Ernie Potts (voice)

Tress MacNeille

Grandma Gertie (voice)

Lou Rawls

Harvey (voice)

Baoan Coleman

Mr. Hyunh (voice)

Mary Scheer

Suzie Kokoshka (voice)

Kath Soucie

Miriam Pataki (voice)

Adam Wylie

Curly Gammelthorpe (voice)

David Wohl

Principal Wartz (voice)

Steve Viksten

Oskar Kokoshka / Smitty (voice)

Maurice LaMarche

Big Bob Pataki / Douglas Cain (voice)

James Keane

Mr. Green / EBN Announcer (voice)

Craig Bartlett

Monkeyman (voice; uncredited)