The archaeological investigation was carried out jointly by the Institute of Cultural Relics of Qinghai Province and the School of Archaeology and Museology, Sichuan University, in July 2021 and October 2023. The new nine microblade sites were discovered along the Ganzi River in Dayu Village, Haiyan County, and the primary cultural layers containing microblade remains were excavated. Archaeological remains from a small-scale the subsequent excavation” included lithic artifacts, animal bone fragments and ground bone tools. The AMS ¹⁴C dating indicates that the site dates back to around 9500 BP cal. This report presents the preliminary results from the investigation and test excavation, providing new evidence for the occupation of the Northeastern Qinghai-Tibetan Plateau by prehistoric hunter-gatherers at the beginning of the Early Holocene. Preliminary research indicates that the lithic technology is dominated by simple flake-core and microblade technologies. Quartzite and chert are the main raw materials. Quartzite containing cortex was found along the bank of the Ganzi River according to the investigations, while the source of chert remains unclear. In terms of the raw material use, chert is primarily used for microblade production, whereas quartzite predominates in flake-core complex. Techno-typological analysis reveals that the flakes were percussion mainly by single-platform cores, with a few double platform cores and core fragments were recovered. The platforms of flakes were mainly natural and plain, indicating a lack of preparation for the flake-core technology. Small size of conical and irregular microblade cores were recovered from the localities. Lithic analysis shows the platforms and flaking faces of microblade cores were frequently rejuvenated. The presence of tablet and over short flakes suggests the complete rejuvenation occurred on the microblade cores. The tools primarily consist of side scrapers, end scrapers and points. Unlike other sites in the Qinghai-Tibetan Plateau, we recovered bone fragments and ground bone tools. Specifically, the ground bone cones and spade were obtained from the test excavation which may indicate the intensive use of the animal bone resource.