Sedimentary cores were taken from the center part of Lake Gucheng, Jiangsu in 2005. The total organic carbon, totalnitrogen, phosphorus, metals were analyzed. Calculations of sedimentation rates were achieved using ²¹⁰Pb CRS method. The resultsdemonstrated that average sedimentation was 0.067 cm/a after 1980s corresponding to that from Chernobyl accident marker occurredat 1986. During the period of 1920s and 1980s, the sedimentation rates varied between 0.056 and 0.167cm/a. The high sedimentationrates found in 1960s may be associated with the intense reclamation since 1960s. Cu, Pb, Zn, Cr showed up-core increase in the to p30 cm sediment. Combined with the ratio of these elements to Ti it was concluded that the origin of Cu, Pb, Zn, Cr was not whollyfrom natural processes. The age was between 6500-8000a BC based on AMS ¹⁴C results from depth 0.5 m to 1.78 m, which wascomparable with OSL age of 7-8 ka from the same depth. Sharp transition of index including TOC, TN and metals emerged at depthof 0.3 m may indicate that sediments could be eliminated due to erosion or human impact such as cultivation. It was reported thatLake Gucheng was isolated from Lake Taihu due to establishment of Xiaba at 1556 A.D. Taken the depth of 30 cm as the timewhen Xiaba was established, the average sedimentation rate was calculated to be 0.067cm/a which was in agreement with theresults of ²¹⁰Pb and ¹³⁷Cs method. Therefore, continual deposition may occur after the isolation of Lake Gucheng from LakeTaihu.