Abstract: Current and future water quality condition of Dapeng Bay was simulated using Delft 3D model on the base of pollutant sources investigation and pollutant load estimation. Water environment capacity of Dapeng Bay was also estimated. The results showed that water quality of Dapeng Bay was good, with exception of water quality degradation in Shatoujiao Sea and Yinzhoutang. It was predicted that pollutant load in all districts will not exceed water environment capacity of Dapeng Bay except Shatoujiao Sea and Yinzhoutang in 2015. It was suggested that Shenzhen and Hong Kong governments should take steps in total pollutant control and society & economy development scheme to ensure that water quality of Dapeng Bay will measure up to water quality standards under both current and future conditions.