Abstract: The sedimentary environment of the Baogutu Formation on the northwestern margin of Junggar basin has been widely discussed. Many authors consider that the Baogutu Formation is shallowsea sediments. This paper systematically studies the sedimentary environment of the Baogutu Formation in this area using the methods of sedimentology, stratigraphic palaeontology, element geochemistry, and so on. It is considered that the Baogutu Formation is mainly shallow to bathyal deposits, and its top and bottom are continental fluvial lithofacies. The Baogutu Formation was formed in the Viseen and Bashkirian of the Carboniferous.