In order to reduce the adverse effect of the project on the estuary environment and improve the ecological effect，we carry out a study on the ecological embankment structure based on the Yangtze estuary south channel regulation phase I project. According to the ecological characteristics of the biological groups in the Yangtze estuary and the engineering influencing factors，we select the large benthic animals as the target biological objects，and analyze the habitat demand characteristics including key indicators of the dominant species. On this basis，we propose a new type of ecological hollow block structure made of porous polyurethane mixture （PPM），and give the design of embankment body structure；in addition，by the method of computational fluid dynamics，we compare and study the layout of blocks. The construction technology of the new hollow block structure is put forward，and the finite element analysis is carried out. Furthermore，the feasibility is verified by the actual construction test.