Based on on-site hydrological，sediment，and topographic data，we analyze the natural conditions，current and sediment environment characteristics，and coastal evolution characteristics of the Daya Bay.The research results show that Daya Bay has a small tidal range，weak wave and current forces.The water body has a relatively low suspended sediment concentration(SSC).The sediment source is limited and the small amount of sediment transported on the beach near the shore is the primary source of sediment in Daya Bay.The surface sediments are primarily composed of clayey silt，which is typical of muddy coastal areas.Due to the clean water and low SSC，weak wave and current dynamics result in the seabed remaining stable for a long time.The recent significant changes in erosion and deposition on the seabed are mainly affected by human activities such as port and waterway construction and land reclamation.Studies indicate that after dredging and excavating the harbor and waterway，the navigation channel remains stable，and siltation intensity is relatively small.A correct understanding of current and sediment environment and beach evolution in the sea area is not only a key technical issue for coastal engineering development and construction，but also beneficial for the protection of nearshore marine environment and resource development and utilization.