Lorne Greene as Grandfather (voice)

Sammy Davis Jr. as Head Ratte (voice)

Margery Grey as Heidi (voice)

Pamelyn Ferdin as Klara (voice)

Michael Bell as Willie (voice)

Peter Cullen as Gruffle (voice)

Roger DeWitt as Peter (voice)

Richard Erdman as Herr Sessman (voice)

Fritz Feld as Sebastian (voice)

Joan Gerber as Fräulein Rottenmeier (voice)

Virginia Gregg as Aunt Dete (voice)

Janet Waldo as Tinette (voice)

Frank Welker as Schnoddle/Hootie (voice)

Michael Winslow as Mountain (voice)

Sue Allen as Chorus (voice)

B.J. Baker as Chorus (voice)

John Richard Bolks as Chorus (voice)

Evangeline Carmichael as Chorus (voice)

Bill Cole as Chorus (voice)

Paul DeKorte as Chorus (voice)

Sandie Hall as Chorus (voice)

Walter S. Harrah as Chorus (voice)

Ronald Harris as Chorus (voice)

Darlene Lawrence as Chorus (voice)

Douglas Lawrence as Chorus (voice)

Shara Lee Lucas as Chorus (voice)

Ida Sue McCune as Chorus (voice)

Gene Merlino as Chorus (voice)

Loulie Jean Norman as Chorus (voice)

Marilyn Powell as Chorus (voice)

Paul Sandberg as Chorus (voice)

Robert Tebow as Chorus (voice)