Abstract: We studied geometries and rates of active thrust faulting and folding in the Aksu Kuche area along the southern flank of the Tianshan Mountains Our fieldwork reveals that the active thrust reaches the surface near the south front of the mountain belt, and that two fault scarps are clearest across terraces and moraines along both sides of the Tailan river in the Tomur area, north of Aksu The inferred their ages for the terraces and moraines, together with heights of fault scarps that cut them, imply a shortening rate of 1 85 mm/a on the Aksu area since Late Pleistocene This rate, similar to that of the Korla area (2mm/a) on its east side and the Kaping area (1 8 mm/a) on its west side, but lower than that of the Kashgar area (10?2 mm/a)farther west and that of the Manas area (6?3mm/a) in the northern margin of the belt, implies that the distribution of shortening across the Tianshan changed markedly along the belt.