Paleosols and sediments are important archives for studying ancient human activities. A soil profile labeled as YC1 was located at Yuchisi, Mengcheng County, Anhui Province, where relics of the Dawenkou Culture and Longshan Culture were detected. Elemental concentrations, such as Pb, Al, as well as the lead isotopes, were analyzed in soil samples collected from Profile YC1. Pb enrichment in the soil layer from 5 050 cal a BP to 4 000 cal a BP, was characterized. Results show that Pb enrichment factors varied from 1.0～1.8 in the cultural layers, and were not quite high. However, with the history going on from the Dawenkou Culture to the Longshan Culture, the Pb enrichment factor displayed an obvious rising trend, which indicated that the Pb in the cultural layers was probably associated with the development of metallurgic activities in the middle stage of the primitive society. From 5 050 cal a BP to 4 000 cal a BP, China underwent Stone Age, Chalcolithic Age and Bronze Age in sequence. Pb dust in the atmosphere increased with intensifying utilization of copper resources, which was probably the main cause of the rising enrichment factor in the cultural layers. The measurements of lead isotope in the cultural layers show the ratio of ²⁰⁶Pb/²⁰⁴Pb varied from 18.3～19.8, with an average being 18.82; the ratio of ²⁰⁷Pb/²⁰⁴Pb from 15.3～16.5, with an average being 15.76; the ratio of ²⁰⁸Pb/²⁰⁴Pb from 38.0～41.0, with an average being 39.04. The tracing study shows the sources of lead in the various cultural layers multiplied from 5 050 cal a BP to 4 000 cal a BP, which was most likely related to ores from South China, including Yunnan, Sichuan, Hubei, Hunan or Guangdong Provinces.