Based on the data of heavy metals( Cu, Zn, As, Hg, Cd, Cr, Pb) in the fluvial sediment of hengyang section of Xiang, including 18 sites in 10 sections, the potential ecological risk of heavy metals was analyzed and assessed by Lars Hanson method. The results showed that order of heavy metal potential ecological risk factor was Cd 〉 Hg 〉 Pb 〉 As 〉 Cu 〉 Zn 〉 Cr in surface sediment of Xiang river ( Hengyang section). The comprehensive potential ecological risk index of a variety of heavy metals was 913.4 RI to show a high ecological risk...