Abstract: Xujiayao(40°06'02.8''N;113°58'41.4''E; ca.970 m above sea level) is an open-air site discovered in 1973 during field reconnaissance by members of the Institute of Vertebrate Paleontology and Paleoanthropology(IVPP), Chinese Academy of Sciences. The site is located on the right bank of the Liyi River and is named after the local village. Scientists from the IVPP excavated Xujiayao in 1976, 1977, and 1979. Xujiayao is represented by two localities(74093 and 73113), with evidence for archaic Homo sapiens, and the majority of the artifactual and vertebrate materials recovered from Locality 74093. The present paper is a preliminary report on the stone artifacts from Locality 74093 excavated in 1977. The Xujiayao site comprises fluviolacustrine deposits, with a stratigraphic profile consisting of a series of erosional surfaces intercalated with eight sandy clay and silty clay depositional layers. Five stratigraphic layers of the 3rd terrace were identified, with a total thickness of more than 15—20 m. Archaeological materials were unearthed mainly from the 3rd layer consisting of grayish green to brown clay(4 m thick). Dating shows that the human activities at this locality most probably took place in the early Late Pleistocene.
A total of 1765 stone artifacts were unearthed from the spit U3 of the excavation in 1977. The stone assemblage includes cores(N=140), retouched pieces(132), flakes(399), flake fragments(427), chunks(667), and stone hammers(2). Lithic materials were locally available from ancient riverbeds with quartzite and vein quartz as the predominant raw material(accounting for 82.6%). The principal flaking technique was direct hammer percussion without prepared striking platforms, together with bipolar technique. Most stone artifacts were small in size,and most blanks for tool fabrication were flakes and flake fragments. More than 10 retouched types were identified, with scrapers and spheroids the most dominant, followed by notches, denticulates, points, burins, scraper-notches, borers, and choppers. Modified pieces were retouched by direct hammer percussion with mostly unifacial retouch on the distal end and lateral margins of the blanks.
The lithic assemblage of this locality shows a close affiliation with the "Small Tool Tradition" in North China.It should be noted that the emergence of spheroids in the lithic assemblage is unique in Chinese Paleolithic studies.

Key words: Xujiayao; Nihewan Basin; Late Pleistocene; Lithics