In this paper, the polarity epochs of some twenty and more sections or boreholes in Qinghai-Tibetan plateau in Late Cenozoic are discussed in detail, and thence we have the ages of the sediments involved. The Qiangtang Formation at Kunlun pass has an age of 3.1MaBP~0.65MaBP, the Hipperion sp. contained in it being of an age of 2.08MaBP.The Gongba Formation at Dingri county 2.31MaBP~1.90MaBP, the Zhada Formation and Xiangzi Formation in the Zhada Basin 6.15MaBP~3.40MaBP and 3.40MaBP~1.25MaBP respectively, and Jiawa Formation at Litang 1.24MaBP~0.43MaBP. And the age for the Hipperion guizhongensis sp. from Jilong is 5.0MaBP. The age of early Quaternary glaciation is obtained as well. Thus a chronological scale is provided for the study of the time, and rate of the uplifting of the Plateau as well as the consequent environmental changes.