Abstract: In order to study the properties of the backscattering coefficient in Taihu Lake,quasianalytical algorithm and optical closure are used in this paper to stimulate the backscattering coefficient of Taihu Lake according to the field measurement data,and its properties and influence factors are also analyzed synchronously.The results indicate that,because of the variation of the suspended sediment concentration,the backscattering coefficient varies over all sampling stations,and the backscattering is mainly caused by the inorganic suspended sediment in Taihu Lake,while the contribution of phytoplankton is slight.The specific backscattering coefficient also varies among the stations,and the variation mainly results from the difference of suspended particle size,shape and composition.Taking 550 nm as reference to parameterize the backscattering coefficient of Taihu Lake,we can find that there is a greater linear relationship between the backscattering coefficient and the suspended sediment concentration,and the exponent index n ranges from 1.32 to 2.8 with a average value of 2.09.