Abstract:A 2D hydrodynamics and pollutant transport model was firstly established, and the model was verified well by the field measured hydrodynamics and water quality data in 2011. Based on this model, the features of hydrodynamics and pollutant transport during a spring tide in the flood season in Qinhuangdao coastal water were studied. Furthermore, the influence of wind on hydrodynamics and pollutant transport in Qinhuangdao coastal water was analyzed. Numerical results show that the main direction of the ebb current is northeast, while the direction of the flood current is southwest. The water level of Qinhuangdao coastal water will slightly decrease under the influence of summer wind in Bohai sea. Meanwhile, the current velocity will decrease in the northern coastal water of Shihe River estuary and increase in the southern coastal water of Shihe River estuary at the slack of ebb, while the current velocity will slightly increase in the northern coastal water of Shihe River estuary and decrease in the coastal water between Daihe River estuary and Luanhe River estuary at the slack of flood. The direction of COD transport is accord with the direction of tidal current. The COD concentration will decrease in the southern coastal water of Luanhe River estuary and increase in the northern coastal water of Yanghe River estuary at the slacks of ebb and flood.