Introduction. The paper discusses some religious beliefs — identified as original and authentic ones — based on shamanic traditions among the Old Barga (Barghuts). Despite the active presence of Buddhism and coexistence with the latter, the Old Barga shamanism remains viable enough. Goals. The study attempts to delineate elements that would indicate connections and interactions between the shamanic tradition of Old Barghuts and those of Buryats and Manchus. To facilitate this, the work pursues a number of objectives, namely: a brief review and analysis of published studies covering the topic; identification of common features inherent to Barghut, Buryat and Manchu shamanisms. Materials and methods. The main research methods employed are the historical/genetic one and that of comparative analysis (with due regard of historicism principles). Results. The available works and materials of different authors, mainly field studies, make it possible to reconstruct the structure and hierarchy of the Old Barga shamanic pantheon, highlight key religious cults that form their unified religious beliefs and preferences. At the same time, publications to have examined the Old Barga shamanism state a genetic relationship with the Buryat tradition — without any essential insights into ideas to be associated with a more archaic layer, and the strong influence of Chinese culture, despite the fact Old Barghuts had been rather placed in Manchu environments. The paper assumes the religious ideas of Old Barghuts which had begun to take shape during the medieval domination of Tengrism (with its central idea of worshiping and deification of the Eternal Blue Sky) also contain and essentially rest on Tengrian views and ideas. Conclusions. So, the Old Barga shamanism is a flexible and changeable system of religious views. However, the transformations experienced nowadays may attest to both its evolution and certain destructive processes.