Abstract: Beach maintenance is the core content of the sandy coast remediation and restoration project and is also a landmark project type for building beautiful bays and beautiful China. For the demand of the supervision technology of beach maintenance project in the sandy coastal areas, the main contents, technical processes and technical points of the supervision work for sandy coastal beach maintenance project are discussed on the basis of analysing the structural compositions of the sandy coastal beach maintenance project. By taking the beach maintenance project in Dolphin Bay of Guishan Island, Zhuhai as an example, the supervisions of the sandy coastal beach maintenance project include the supervision of the beach replenishment project and that of the embankment project. The key technical indices for the supervision of the beach replenishment project include the volume, particle size and environmental quality of sand replenishment, the elevation and width of beach shoulder, and the slope of tidal beach, and those for the embankment project include the length, width, position and orientation and wave resistance strength of dam and the elevation of dam top. The on-site supervision of the technical indices mentioned above can not only provide a guarantee for the quality and quantity guaranteed construction of the beach maintenance project in Dolphin Bay, but also offer a technological reference for the supervision of beach maintenance projects in the sandy coasts of China.