The Mangas (Mong. ‘demonic creature’) has unique characteristics and appearances, so its image has long attracted the attention of numerous scholars. As a result, the question of origins of the Mangas’s multiple heads has been a point of active disputes. So, the multiple heads make the one of the most important problems of Mongolian folklore that scholars are inclined to study. Scholars expolre the origins of the multiple heads by means of cultural anthropology and religious studies. However, the Mangas may have both one head and multiple ones. The image of the one-headed Mangas actually prevails in the Mongolian oral tradition. In most compositions of the Barag epic, the Mangas are one-headed. In the Jangar epic, the Mangas may have more than one head and often denote foreign emperors and rulers. In the Oyirad tradition of China, ‘Mangas’ stands for a man — strong, stout-herted, and courageous. More than anywhere else, the Oyirad people have largely maintained their traditional culture, including the Jangar epic. So, the image of Mangas can be compared to human images. And how does traditionally a Mangas look like? On the one hand, we can find the answer from historical literature, such as The Secret History of the Mongols. In it, the Mangas is discribed like a human being. On the other hand, the image of Mangas is very close to that of Cyclops widespread enough in Europe, Central and East Asia, Northeast Asia, e. g., in Turkic cultrue. Thus, the Mangas might be connected with Cyclops in terms of origins. In Mongolian oral literature, Mangas also have multiple heads, and this image can be compared to demonic beings from Indian and Tibetan folk literatures, with their negative role in the religious system of Buddhism. So, the multiple-headed image also prevails widely in Indian and Tibetan cultures. There are also variants of the image of Mangas. But so far scholars have focused only on the multiple heads of the mythological character and ignored the one-headed image. The problem of relationship between the multiple-headed demonic creature and the one-headed one is still understudied. This paper discusses the physical characteristics attributed to the Mangas before, and traces the transformation of its appearances in later Mongolian folk literature. Finally, the article attempts to discribe the reasons behind the changes in the image of the Mangas.