Abstract:The concentrations of acid volatile sulfide (AVS) and simultaneously extracted metals (SEM) were analyzed in 16 surface sediment samples (0-5 cm) from Lake Fuxian. The potential ecological risks of heavy metals were also evaluated by the molar ratio of ∑SEM to AVS. Results show that obvious distinction of AVS distribution are existed in the south and north lake zone. There is uniform distribution in the south lake zone which has an average AVS concentration of 0.074±0.043 μmol/g. However, the north lake zone displays a increasing trend from the littoral to pelagic area (N9) and has an average AVS concentration as high as 0.317±0.485 μmol/g. SEM is mainly concentrated at two points, Laoaodi (N5) and Dongda River estuary (N4) in the north lake zone. As for the south lake zone, SEM is mainly concentrated at S2, Luju River estuary. With the exception of Niumo River estuary (S5), Liangwang River estuary (N3) and N9,[∑SEM]/[AVS] of all the remaining sites are higher than 1, and the average[∑SEM]/[AVS] in south lake zone (3.51±1.91) significantly exceeds that in north lake zone (2.19±2.10). Therefore, ecological risk in Lake Fuxian especially in south lake zone should be taken seriously.