The Karamaili Mountains are located in the eastern part of Junggar Basin. Late Paleozoic Karamaili ocean subducted to the north and the Siberian plate collides with Junggar plot in this area. At present, there are many views on the tectonic activity of the Karamaili Mountains after the Carboniferous period, such as continuous extrusion, sliding, stretching, extrusion-stretch conversion, and their tectonic styles are also different. In this paper, we pay a lot of attention to the tectonic styles and study them applying theories of fault-related fold to explore the mountain-basin coupling mechanism of the southern margin of the Karamaili Mountains. The results show that the Karamaili Mountains experienced 6 tectonic uplifting activities after the Carboniferous period, such as Middle Permian, Early Triassic, Late Triassic, Late Jurassic-Early Cretaceous, Late Cretaceous and Late Paleocene. The first four periods were dominated by differential uplift. In the Early Cretaceous period, the formation of the Paleozoic strata along decollement, the bottom of the Lower Permian strata, wedged into the south, and the reduction was more than 15 km. After a long time denudation, the wedges were destroyed by break-through fault behind in the Eocene. Since the beginning of the Oligocene, large-scale tectonic activities have occurred no longer in the Karamaili Mountains. After a long time denudation to now, the present geological structure is formed finally.