The film begins with animation. A plane headed for "Bukuvu, the Heart of Africa" crashes, losing infant George to the jungle. 25 years later, George is a noble savage of a man. However, George isn't alone, his friends include: talking gorilla "Ape," "Tookie" the toucan, "Little Monkey" the capuchin, and African elephant Shep, George's "dog."
Live action kicks in with Ursula exploring the Bukuvu jungle with help from Mr. Kwame and some porters. She's wandered Africa alone, but her fiance Lyle and a pair of poachers, Max and Thor, track her down. The evening features Mr. Kwame telling of the White Ape, a mythical primate who rules the jungles.
The following day, Lyle nearly kills a porter and even abandons Ursula to a lion. George rescues Ursula, bringing her to his treehouse, while Lyle returns to camp and says the White Ape attacked. While the rescue party hunts for Ursula, George teaches her to swing from vines, falling for her. Ape recommends George should woo her as a gorilla, but it's George's natural charm which wins her heart.
On the day after, the party finds George's place, Lyle discharges his weapon and hits George's arm as George tries to stop Max and Thor from tranquilizing Ape. Lyle is arrested and George is flown to Ursula's home, San Francisco, for medicine and clothing. Ursula finally confronts her parents about Lyle, but her mother demands Ursula marry a man of wealth and class.
Elsewhere, Max and Thor capture Ape. Ape sends Tookie to get George. George heads to Africa, with Ursula soon following. George encounters the poachers in his treehouse, with Ape caged and defeats them with help from his friends. However, Lyle appears now as a member of a marriage cult and kidnaps Ursula, intending to marry her immediately. George pursues along rapids, saving Ursula as Lyle enters a dark tunnel. Lyle emerges, now wed to a gorilla. George and Ursula wed and ride away on Shep, later having a son.