²¹⁰Pb, ¹³⁷Cs and ²⁴¹Am were used to analyze the sediment core of Lake Fuxian. In the core, there were obvious peakscorresponding to 1963 and 1986, verifying the existence of peak recorded in 1975,which was important age mark for the Lake Fux-ian sediment. The sedimentation rate of the Lake Fuxian was 0.063g/cm².a by ¹³⁷Cs time marker(1963),0.052g/cm².a by¹³⁷Cs time marker(1975)and 0.039/cm².a by ¹³⁷Csyears. ²⁴¹Am dating can improve the accuracy of peak in 1time marker(1986),which indicated a slower process in the past 50auPh(CRS) dating showed a little deviation from ¹³⁷Csexplaining the reasons in different viewsThe limit mass depth was 7.366g/cm².a,which corresponded to the age of 1878 dating The average sedimentation rate from 1878 to 2007 was 0.057/cm².a,which was changeable in the Lakc h'uxian by analyzing the massages, which showed that the sedimentation environment was related to human disturbance in the depth and past 129 years.