North Tarim peripheral foreland basin, developed from early Carboniferous to early Triassic, recorded the development course of South Tian shan orogenic belt. This basin transited from flysch to molasse, and migrated southward for a long distance at the end of early Permian. Moreover, at the same time, magmatic activity forming the igneous rock with no Eu-anormaly and mantle materials, whole uplift ofSouth Tian shan orogenic belt, hydrothermal deposits, and intensive metamorphism. and deformation took place simultaneously. The coincidence of these geologic events suggests they are all related to a same geologic mechanism; subducted slab breakoff. So, it is thought that the flysch to molasse transition of North Tarim foreland basin may be one response to slab breakoff. Many other orogens, such as Qinghai and Tibet orogen, all exhibited those characteristics, suggesting that slab breakoff may be an integral part in orogenic movement.