Abstract: In order to better understand the typical pollutants contamination and potential ecological risk of sediment in main bays of Zhejiang. The contents of typical pollutants(PCB, Hg, Cd, As, Pb, Cu, Cr and Zn)in the sediment of Zhejiang bay were evaluated, adopting the index number techniques of single factor and Hakanson ecological risk. The order of integrated contamination degrees was Yueqing bay(12.14) > Wenzhou bay(11.90) > Taizhou bay(11.36) > Sanmen bay(10.53) > Xiangshan bay(9.90) > Hangzhou bay(9.87), with moderate degree of contamination. The main pollutants were Cd and Cu in each bay. The order of potential ecological risks was Hangzhou bay(157.04) > Wenzhou bay(154.86) > Xiangshan bay(148.09) > Sanmen bay(146.24) > Taizhou bay(145.86) > Yueqing bay(145.56), with moderate ecological risk in Hangzhou bay and Wenzhou bay, and low ecological risk in other bays of typical pollutants contamination. The major risk factor of sediments in Hangzhou bay, Xiangshan bay, Sanmen bay and Wenzhou bay was Cd and Hg, in Yueqing bay was Cd and Cu, and in Taizhou bay was Cd and PCB.