Based on the FVCOM(Finite-Volume Coastal Ocean Model)model,a detailed 3D tidal current numerical model of Minjiang Estuary area is established.The selection of subsea drag coefficient is discussed,and the conclusion of Koutitas formula is more reasonable.The tidal and tidal current characteristics of Minjiang Estuary are analyzed by using this model.It is concluded that:Minjiang tidal wave spreads from the southeast to the northwest to the estuary area,and the flow within the channel has obvious reciprocating flow characteristics.Tidal current mostly tend to rotating flow-based in north and east of the Yundou island.The north branch of the Minjiang river is dominated by falling tide,and the 3D flow field in estuary area is not obvious in the influence area of lateral tributaries.