The north foreland of East Kunlun Mountains, located in south Qaidam Basin, has experienced dual events of the uplift of East Kunlun Mountains and the strike-slipping of the Altyn Tagh fault since Mesozoic and Cenozoic period. Based on the new interpretation of the seismic data and other data as well as studies of the structural characteristics, activity properties and epochs and the control of the main faults over oil and gas resources in the study area, the authors hold that the north edge fault of East Kunlun Mountains was related to the uplift of the Kunlun Mountains and the activity of Altyn Tagh fault. The early stage of Miocene and the last phase of Early Pleistocene were main faulting active stages. Therefore, it is likely to find the same type oil and gas reservoirs in the Qaidam Basin through the study of the evolution of East Kunlun Mountain fault.