| Lorne Greene | Grandfather |
| Sammy Davis | Heat Ratte |
| Margery Gray | Heidi |
| Michael Patrick Bell | Willie |
| Peter Cullen | Gruffle |
| Fritz Feld | Sebastian |
| Pamelyn Ferdin | Klara |
| Joan Gerber | Fraulein Rottenmeier |
| Richard Erdman | Herr Sessmann |
| Virginia Gregg | Aunt Dete |
| Janet Waldo | Tinette |
| Frank Walker | Schnoddle/Hootie |
| Michael Winslow | Mountain |
Technical Credits
| Robert Taylor | Director,Screenwriter |
| Hal Ambro | Animator |
| Joseph Barbera | Producer,Screenwriter |
| Jameson Brewer | Screenwriter |
| Hoyt Curtin | Score Composer |
| Charlie Downs | Animator |
| William Hanna | Producer |
| Paul Julian | Art Director |
| Burton Lane | Songwriter |
| Gregory V. Watson | Editor |