Abstract: The Carboniferous deposits which contain commercial oil and gas are well-developed in Northwest China. What kind of the basins would be in the depositional period attracts so many geologists. In terms of sedimentary characteristics, palaeotectonic configuation, palaeo-oceanography and palaeo-climate, the author suggests that the primary factors controlling the sedimentation of the Carboniferous basins in the study area include sea level fluctuation, palaeoclimate background and tectonism among which the latter is the most important. According to the above-mentioned factors, three sedimentary facies(nonmarine, transitional and marine facies), three palaeoclimatic zones (subtropical, temperate and subfrigid zones)and three tectonic types(ocean crust, transitional crust and continental crust types)have been distinguished for the basins. A comprehensive name was then given to a certain basin. This classification is easy not only to name but also to correlate. Therefore, it is helpful to the prediction of the occurrence of the basin sediments, siratabound deposits, especially oil and gas resources.