To determine the optimal layout scheme for the regulation buildings in the South Passage of the Yangtze Estuary and achieve effective regulation outcomes,this paper employs a three-dimensional sediment-water mathematical model to systematically compare and optimize the layout of these buildings.On the basis of the complex hydrodynamic and sediment transport characteristics of the South Passage alongside its riverine conditions,this paper follows a regulation approach concentrated on “bank protection,channel stabilization,flow diversion,and sediment retention”,and designs a multi-stage comparison and selection process.Starting from the initial scheme,the NCG1A scheme restricted flow in the lower section of the Jiangya North Channel is identified as the preferred option.Subsequent comparisons of different scheme configurations reveal that eliminating the north and south jetty clusters while optimizing only the diversion embankment axis offers greater advantages in enhancing main channel dynamics,ensuring navigation safety,and minimizing environmental impact.Further refinement of embankment elevation and length determine that a crest elevation of 2.0 m yields optimal channel regulation,with the embankment length optimized to 24.4 km.Scheme NCG5 effectively enhances the ebb-tide dynamics of the southern main channel while minimizing impacts on the adjacent northern deep-water channel and Jiuduansha Nature Reserve.This achieves synergistic multi-objective coordination of navigation channel management effectiveness,navigational safety,engineering economics,and ecological conservation,providing valuable insights for similar estuary regulation projects.