Abstract: Hangzhou Bay traditional dike is typical in China. It has a long history, rich type and perfect system. It is also the basic infrastructure of Hangzhou-Jiaxing-Huzhou Plain and Ning Shao Plain in flood control. From the perspective of landscape architecture, this paper sorts out the historical evolution of the construction of seawalls in the Qiantang River estuary area. Then it summarizes the dike construction system in terms of the main dike type, related ancillary structure and architecture. It gives priority to analyzing the support effect of dike on the traditional human settlement environment in the southeast coastal area, especially the relationship between the dike and the canal system, the dike and land layout, and the dike and settlement structure. This is of great significance to understand the formation and morphological structure of the lowland landscape in southeast China.