Located in the northeastern Qinghai—Xizang (Tibetan) Plateau, the deformation of the Xining basin in the Cenozoic shows obvious characters of stages, in the Early Cenozoic, the basin underwent clockwise rotation, resulting in the formation and reactivation of NNWtrending leftlateral strikeslip faults in the basement. In the Late Cenozoic (since the Miocene), due to the strong and continuous activation of the boundary faults of the basin and rotation to some extent of the basin, a series of NNE and NEstriking minor faults cutting the basement developed. The formation of the faults of different directions and stages in the basin is similar to that of transpression deformation. And thinskinned and thickskinned structures all character the deformation of the Xining basin, not only did the cover layers undergo folding to some extent, but also the basements of the basin were uplifted to the surface along some faults, resulting in the formation of basementinvolved anticlines. And due to the activities of these faults, the basin was dismembered into some small subbasins. And the deformation of the northeastern Qinghai—Tibetan Plateau also has similar characteristics; transpression deformation is an important style of deformation in the region. Just because of long term transpressional action, strain was partitioned between the interior of the basin and its boundary faults, the basement of the basin uplifted and dismembered the early larger basin. The Reshui—Riyueshan and Wenquan faults took place in the step between the Haiyuan fault to the north and the Kunlun fault to the south, the development of them has close relations with these large boundary faults，and these are also important characteristics of transpression.