The local landform will be changed after reclamation through sea-dike building.It will affect the character of tide and tidal current,and the sediment transporting near the reclamation region.Taking the shore reclamation between Oujiang and Feiyunjiang Estuary as example,a tidal current mathematical model was used to study the effects of the hydro-dynamic environment due to the large-scale reclamation.Based on triangle grid and finite volume method,the flow model was examined by observed tidal level stations and synchronous vertical lines.Tthe comparison between computed result and measured solution showed very good agreement.After the project building,the high tide level reduced to some extent and the flow of front reclamation line reduced by a big margin.But it had a little influence on the core ports of Wenzhou.And the tidal influx through Feiyunjiang Estuary kept decreasing.The result can be used as a reference and inspiration for the effects of the large-scale reclamation projects on hydro-dynamic environment.