Gucheng Lake, situated in the southeast of Gaocheng County, Jiangsu Province, surrounded by mixed evergreen/deciduous broad,leaved forests, lies between the north and middle subtropical zone in monsoon Asia area.This paper deals mainly with the systematic palynological research on more than 57 samples from a column core with a depth of 6.2m in Gucheng Lake.According to the spore-pollen diagram, 8 assemblage zones have been distinguished in an ascending order as followss 1.Cyclobalanopsis-Casianea-Liquid ambar zone(6.3-5.lm);2.Pinus-Querous-Polypodiaceae zone (5.1-4.15m);3.Cyclobalanopsis-Graminea-Typha zone (4.15-3.2m);4.Greunines-Artemisia-Quercus zone(3.2-2.3m);5.Quercus-Pinus-Castaned zone (2.3-1.75m);6.Graminea-Artemisia-Quercus zone (l.75-1.lm);7.Quercus-Pinus-Caslanea zone(l.1-0.45m);8.Pinus-Graminea-Artemisia zone(0.45-0m) From the above statement, 8 phases of the paleovegetation succession and climate fluctuation seem to be shown in the past 4000 years, and 8 climate periods can be listed in the ascending order for convenience of correlation: 1.3700-3000 a B.P.: warmer and moist;2.3000-2500 a B.P.: temperate-cool and a little wet;3.2500-2000 a B.P.: warm and wet;4.2000-1500 a B.P.: temperate-cool and a little wet;5.1500-1000 a B.P.;warm and wet;6.1000-800 a B.P.: temperate-cool and a little dry;7.800-500 a B.P.;temperate and wet;8.500a B.P.-present: cool and a little dry.Moreover, according to the analysis of stable carbon isotope of organic matter, TOC, diatom and historical records, the influence of climate and human activity on environment is also discussed.