Abstract: The sand dunes on the eastern shore of the Qinghai Lake are distributed over three areas,namely over riparian plain of the eastern of the lake, the Sand Island and the sand bank inside the lake as well as over the divide area of Daotang River, occupy approximately an area of 475 km. The dune types are mainly star dune and barchan and are characterized by dense distribution and big scale. The sand materials supply comes mainly from the alluvial-lacustrine deposits of the Recent epoch in valley-mouth delta in western and northern of the lake, and they are blown to accumulate on the eastern shore of the lake. The lake was in a condition of high lake surface during the Later pleistocene epoch and the aeolian sand deposits are formed since the Early Recent epoch along with the lake contracts. The aeolian sanb was occurred in two periods of dry and cold, i.e. cold period and neoglacial period in the Early Recent epoch. A period of warm and wet has been represented by the fossil soil bed between new and fossil dunes in both above-mentioned periods. It is found from the dating of C¹⁴ that the fossil soil bed was formed before 3960±100 years.