Abstract: During a systematic archaeological investigation from June to July 2009, six sites were discovered in the Tibetan Plateau marginal region. A large number of archaeological remains such as stone artifacts, broken animal bones, hearths, and charcoal was unearthed. The stone artifacts consisted of cores, flakes, chunks, microblade cores, microblades, and retouched tools. Some of the scrapers were retouched in great detail. The stone assemblage of this region shows that the flake industry and microblade industry were used synchronously at the majority of sites.
Some charcoal collected from the hearths yielded radiocarbon dates. For example, the age of Yantaidong(also called "Ten Hearths") was about 10360±60 BP, and Baifosi(also called "White Buddha Temple") was dated to 4280±40BP.Based on evidence from the sites discovered in this region, we suggest that humans move into Tibetan Plateau gradually. This region provided humans with an extensive and broad spectrum of foodstuffs, opportunities for tool-making technology, access to natural resources and warm and wet conditions during the interglacial stage.
Between 40-25ka BP(last interglacial),the climate was moist and warm, which gave humans the opportunity to move into the region. There is some archaeological evidence that clearly showed a human presence in this region around 30ka BP, in the form of seasonal resources. The Lenghu Locality 1 and Xiao Qaidam Lake are possible sites dating to this time but there still needs to be further of this time period.
Between 25-18ka BP(Last Glacial Maximum), the cold and dry climate offered poor living conditions, which lasted to 15ka BP. No human remains have been found from this period, but after 15ka BP, the climate of the Tibetan Plateau became suitable for humans. A few sites have been found, and some such as Heimahe and Yantaidong suggest a type of social and foraging organization involving multiple family groups occupying the location for an extended period of time, probably for seasonal use.

Key words: Prehistory; Tibetan Plateau marginal region; Survey; Excavation