To establish a database on toxic contaminants in Jinhae Bay and Gwangyang Bay, 49 sediment samples were collected and analyzed. Sediment cores were also collected to evaluate the background levels of heavy mentals in Masan Bay. In Jinhae area, intensive sampling was conducted in Masan Bay this year. Organic contaminants and heavy metals in surface sediments were distributed widely in both the bays. In general, the contamination level of Masan Bay was hogher than that of Gwangyang Bay. In Masan Bay, inner part of the bay and sewage treatment plant(STP) outfall was identified as major pollution sources of toxic sebstances.