Hans Conried
as Narrator / Horton / Dr. H. Hoovey (voice)
June Foray
as Jane Kangaroo / Mother Who / Baby Who / Cindy Lou Who (voice)
Chuck Jones
as Junior Kangaroo / Various Whos / Quizmo McKwoff / JoJo (voice)
Thurl Ravenscroft
as Wickersham Brother (voice) (uncredited)
