Full cast of Robot and Monster

Curtis Armstrong

Robot DeFault / Marf (voice)

50 episodes

Harland Williams

Monster Krumholtz (voice)

50 episodes

Maurice LaMarche

Gart / Perry / Loudmouth (voice)

50 episodes

Jonathan Slavin

Ogo (voice)

50 episodes

Megan Hilty

J.D. (voice)

50 episodes

Cree Summer

Spitfire / Globitha (voice)

50 episodes

Rhea Perlman

Nessie (voice)

50 episodes

Fred Tatasciore

Punch Morley (voice)

50 episodes

Kurtwood Smith

Mr. Wheelie (voice)

50 episodes

Ping Wu

Master Grabmirist (voice)

50 episodes

Nolan North

Hal Worth-a-ton / Uncle Kuffley / Crikey (voice)

50 episodes

Jeff Bennett

Snap Winsome / Lil' Lugnuts (voice) / Snap Winsome (voice) / Marf (speaking) / Snap Winsome (voice)

7 episodes

April Winchell

Arpa / Grandma 10010 (voice)

4 episodes

Jennifer Cody

Lucy (voice)

3 episodes

Alan Tudyk

Crazy Cousin Gizmo (voice)

2 episodes

Bill Fagerbakke

Lev (voice)

2 episodes

Ruth Williamson

Dame Lady Madame (voice)

1 episode

Jon Polito

Sir Cranklin (voice)

1 episode

Rob Paulsen

Bob / Scale (voice)

1 episode

Jeffrey Tambor

St. Crispy (voice)

1 episode

Leon Thomas III

Monster's Singing Voice (voice)

1 episode

Kari Wahlgren

Robo Ono (voice)

1 episode

Greg Cipes

Vapid Milquetoast (voice)

1 episode

Harriet Sansom Harris

Bea Holder (voice)

1 episode

Adam Wylie

Fuzzy Slippers (voice)

1 episode