Lingdingyang is the horn shaped estuary in which the four east gates of Pearl River injected,with runoff-tide confluence and complex dynamic. From the aspects of tide level,velocity,flow and power pattern,the impacts of the Shenzhen-Zhongshan channel project on flow environment of Lingdingyang estuary are studied by mathematical modeling.Results show that:the impacts on the hydrodynamic environment of the west artificial island are the greatest,while the impacts of the anchorage and main piers take the second place,and there will be no great changes near the east artificial island and non-navigable bridge pier.Anymore,the variation of tide level and flow field in the vicinity of the island and the bridge is obvious.Overall,the Shenzhen-Zhongshan channel project has little impact on the overall pattern of the Lingdingyang estuary.