In order to understand the source of heavy metals in river sediment and their impacts on the local environment, we adopted potential ecological risk index method to evaluate the heavy metal pollution of a town in central Jiangsu Province, then Pearson correlation analysis and R-type cluster analysis to analyze the source of the pollution. Results showed that the average contents of Hg, Cd, As, Cu, Ni, Pb, Cr and Zn were 0.41mg/kg, 0.36 mg/kg, 12.04 mg/kg, 43.26 mg/kg, 48.77 mg/kg, 35.95 mg/kg, 108.11 mg/kg and 140.30 mg/kg, respectively. Among them, Hg and Cd were the most harmful and heavily spread pollutants, Cd pollution was mainly related to smelting, fossil fuel combustion and coating industry, Hg was induced by the fossil fuel combustion, Cr mostly came from the manufacture of alloy products, Cu and Ni were associated with electroplating process, and As and Zn were mainly related to the chemical manufacturing.