- Bessie Love
- Paula White
- Lewis Stone
- Sir John Roxton
- Wallace Beery
- Prof. Challenger
- Lloyd Hughes
- Ed Malone
- Alma Bennett
- Gladys Hungerford
- Arthur Hoyt
- Prof. Summerlee
- Margaret McWade
- Mrs. Challenger
- Bull Montana
- Ape-man
- Frank Finch Smiles
- Austin
- Jules Cowles
- Zambo
- George Bunny
- Colin McArdle
- Charles Wellesley
- Maj. Hibbard
- Jocko the Monkey
- Jocko - the Monkey
- Arthur Conan Doyle
- Sir Arthur Conan Doyle
- Mary the Chimpanzee
- Mary - the Chimpanzee
- Malcolm Denny
- Undetermined Secondary Role
- Virginia Brown Faire
- Marquette - Half-Caste Girl
- Holmes Herbert
- Undetermined Secondary Role
- George Marion
- Old Professor
- Nelson McDowell
- Lawyer Advising the Editor
- Jack Murphy
- Office Boy
- Robert Page
- Policeman
- Gilbert Roland
- Undetermined Secondary Role
- Leo White
- Percy Potts
