Ross Bagdasarian, Jr.

as David Seville / Alvin Seville / Simon Seville (voice)

Janice Karman

as Theodore / Brittany / Jeanette / Eleanor (voice)

Dody Goodman

as Miss Rebecca Miller (voice)

Susan Tyrrell

as Claudia Furschtien (voice)

Anthony De Longis

as Klaus Furschtien (voice)

Frank Welker

as Sophie / Native Chief / Baby Penguin / Additional Voices (voice)

Nancy Cartwright

as Arabian Prince (voice)

Philip L. Clarke

as Additional Voices (voice)

Ken Sansom

as Inspector Jamal (voice)

George Poulos

as Additional Voices (voice)

Charlie Adler

as Additional Voices (voice)

Patrick Pinney

as Additional Voices (voice)

Jack Angel

as Additional Voices (voice; uncredited)

Mel Blanc

as Additional Voices (voice; uncredited)

Laura Summer

as Additional Voices (voice; uncredited)