In the imperial era, Japanese children’s culture had depicted Africa and the South Sea Island as dangerous and marginal regions where wild beasts and “barbarians” lived and aggressively threatened visitors that came from civilized areas. Since Imperial Japan lost WWⅡand the Allied Forces, mainly the United States, occupied Japan, Japanese society has accepted various kinds of influences from the United States. The children’s culture also adopted several American characters, such as Tarzan, and gave new forms to cultural imagination, which connected new Americanism and prewar colonialism. The purpose of this paper is to examine how the postwar children’s culture maintained/deconstructed the colonial imagination toward marginal regions, such as Africa, focusing on Tezuka Osamu’s The Jungle Emperor, which had been serialized in the magazine the Manga Shonen from 1950 to 1954. In this manga, Tezuka narrated various adventurous stories and depicted Africa as “the Dark Continent,” which is similar to other works in the children’s culture. But simultaneously, he allegorically exhibited a resistance to such a typical representation of Africa by adopting a lion as the protagonist. Therefore, this paper aims to analyze how Tezuka inherited and deconstructed such a colonial imagination, formed and flourished in the imperial era, and clarify the cultural significance of this text in the history of Japanese children’s culture.