The northeastern margin of the Tibetan Plateau is the leading edge of the expansion of the plateau from south to northeast, and its Cenozoic tectonic deformation is of great significance for revealing the upward and outward expansion processes and dynamic mechanism of the Tibetan Plateau. The Qaidam basin is the largest Cenozoic sedimentary basin along the northeastern margin of the Tibetan Plateau, it contains huge thickness Cenozoic strata with bulk information for plateau growth. The vertical- axes rotations recorded by these strata carry quantitative constraints on the time, mode and amplitude of Cenozoic tectonic deformation in the Qaidam basin since Cenozoic. Here, we studied vertical- axes rotations of the Lulehe section in the northern margin of the Qaidam basin, where Cenozoic strata are well exposed and controlled by precise stratigraphic age. The Characteristic remanent magnetization directions (ChRM) of 1477 reliable paleomagnetic samples from 24. 6 to 5. 2 Ma along the Lulehe section was statistically analyzed. It is found that the Lulehe area had undergone a small (insignificant) counterclockwise rotation with 8. 4°±6. 1° during 24. 6 to 16. 4 Ma. From 16. 4 to 13. 9 Ma, the Lulehe region was significantly clockwise rotated with 36. 10°±6. 0°. No significant tectonic rotation occurred in the region during 13. 9 to 5. 2 Ma and ~6° counterclockwise rotation recorded after 5. 2 Ma. Combined with the analysis of deformation in the northern Qaidam basin, we attribute middle Miocene ~36°clockwise rotation in the Lulehe area at the northern Qaidam basin to crustal differential shortening deformation, which drove the outward growth of the Tibetan Plateau to its north margins.