The Nantaizi site is located in the northeastern part of Yu County, Zhangjiakou City, Hebei Province, within the central-eastern Yuxian Basin, which lies in the southern part of the broader Nihewan Basin in northwestern Hebei. In 2013, the Hebei Provincial Institute of Cultural Relics and Archaeology and other units excavated an area of 20 m², revealing three phases of cultural remains. The upper cultural layer dates to the Warring States-Han period. The middle cultural layer yielded microblade technology stone artifacts; based on the stratigraphy and lithic assemblage, these are estimated to approximately 20,000 years ago. According to the ¹⁴C dating results, the age of the lower layer is 33 ka before present, and 58 burnt stones and 74 stone artifacts were unearthed. The stone artifacts belong to the core-flake technology type, characteristic of the main industry dominated in northern China, representing the latest stage of core-flake technology in North China. The burnt stones may be remnants left from the “stone boiling” method used in the Late Paleolithic to heat water or liquid food, providing important clues for exploring fire-use behaviors of Late Paleolithic humans. The site is situated at a critical stage of the Late Paleolithic lithic technological transformation in North China. The discovery of core-flake and microblade technologies in stratigraphic superposition from the early to late layers holds significant value for exploring the relationship between core-flake technology and microblade technology in Northern China, as well as the emergence of the latter.