A series of old orogenic belts and basins were rejuvenated in the context of Cenozoic India- Asia convergence forming in the periphery of the Tibetan Plateau the largest intracontinental compressional zone, which is named as the circum- Tibetan Plateau basin and orogen system (CTPBOS). The formation process and underlying mechanism of the CTPBOS are of large significance in advancing our knowledge of how continental collision impacts deformation in the interior of a continent. The Qaidam basin is an important Cenozoic sedimentary basin in West China, and bordered by huge orogenic belts. They together form the main body of the northeastern part of the CTPBOS. In this study, we combined the upper- crustal and deep (Moho) deformation through latest exploration seismic data, surface geology and published deep geophysical imaging, portrayed the structural coupling between the Qaidam basin and the three surrounding orogenic belts in the lithospheric scale, and accordingly explored the basin- mountain convergence process and underlying mechanism of the CTPBOS. In upper- crustal scale, a set of basement- involved, high- angle reverse faults developed in the conjunction regions of the Qaidam basin and the Qiman Tagh- East Kunlun Shan to the south and the South Qilian Shan to the northeast. These faults, which generally dip toward the mountains, are dominated by vertical basement rise with limited horizontal shortening, and were initiated in the Early Cenozoic. In the lower crust and lithospheric mantle, deep faults dipping toward the basin developed and offset the Moho of the Qaidam basin and adjacent mountains. These observations imply lithospheric- scale wedge tectonics, which are characterized by the Qaidam lithosphere tapering into the thickened lower crust of the Qiman Tagh- East Kunlun Shan and the South Qilian Shan, and formed in response to the lateral heterogeneity of the lithospheric strength between basins and orogenic belts. Different from the above contraction- dominated basin- orogen systems, the Qaidam basin and the Altyn Shan to the northwest are simply separated by the huge sinistral lithospheric- scale Altyn Tagh fault, which served as the lateral slip boundary during the formation and deformation of the Qaidam basin.