By analysis of published papers on the Yangtze estuary and hydrological and sediments datain Yangshan Harbor area, many similarities are found between Yangshan Harbor area and the Yangtzeestuary. These similarities include the phenomenon of stagnating flow areas, the distributivecharacteristics of the highest suspended sediment concentration areas, superficial sediments and shoalbars. The stagnating flow area is the major similarity which causes other similarities. These similaritiesindicate that: 1) Turbidity Maximum and mouth bars in estuaries are mainly caused by the hydraulicbalance of stagnating flow areas of estuaries; 2) The stagnating sand area of sands caused by stagnatingflow area often locates on the narrower side of the stagnating flow area; 3) The location (or shape) offine sediments area caused by stagnating flow area reflects the location (or shape) of the stagnatingflow area. Both Yangshan Harbor area and the Yangtze estuary are the important developmental areasin the future (man-made similarity). In-depth studies on these similarities between Yangshan Harborarea and the Yangtze estuary will have momentous theoretical and practical significance.