According to the analysis on TOC,TN.pigment,organic carbon isotope.HI and "Cdating etc. obtained from the sedim ents of a 3.96m-long core in W est Taihu Lake、it ispossible to understand the evolution of paleoenvironment during the last 14000 years inTaihu Lake. The results show that the evolution of paleoenvironment has undergone thefollowing stages:Before West Taihu Lake was formed.there existed exposed feature fromthe proxies in l 4300-13000aBP.reflecting arid paleoclimate.After the lake was formed.the climate got CO0l in 13000~ l 1030aBP. All proxies showed a distinct cold and wetterclimate in l1030~ 10200aBP. It was a warm and dry period in 10200-9500aBP.and thenturned into a transitional stage of warmer and wetter climate with drastic fluctuation.It waswarm and wet during 7200-5700aBP,Some proxies changed violently in 570O-4900aBP.reflecting a probable interruption of sedimentation. The lake began to be eutrophic in4900aBP or later.