The large left lateral strike- slip faults are responsible for the continental deformation of the Qinghai- Tibet Plateau. Recent studies on the Altyn Tagh fault have called attention to the growth of the northern edge of the Plateau. Field survey and previous results suggest that the slip rate of the Altyn Tagh fault abruptly decreased on two sides of the triple junction from the Subei County to the Shule River. The thrust faults, strike faults in the western segment of the Qilian Mountain have absorbed the sinistral displacement of the Altyn Tagh fault, and thus the present trace disappeared in west of Jiuquan basin. But the Altyn Tagh fault had extended into the Alxa block before mid- Miocene. The Plateau began to extend laterally along the Altyn Tagh fault at the almost same slip rate after collision between the Kohistan and Eurasian plates, and there is no obvious uplift on both sides of the fault. Then, the East Kunlun and Qilian orogenic belts prominently uplifted successively, and the lateral extension of the Altyn Tagh fault rapidly decreased. Therefore, a coupling interaction exists between the extrusion of the Altyn Tagh fault and the uplift of the East Kunlun and Qilian orogenic belts.