Abstract: The beach in the Beiliukou section of Shidao Bay is a typical barrier-lagoon coast.There used to be large natural high-quality beaches.Affected by marine disasters such as storm surges and human activities,the change in the dynamic environment of the bay has led to continuous erosion of the beaches,and the coastal ecological environment has been damaged to varying degrees.Taking the Shidao Bay coastal zone as an example,combined with historical remote sensing image data,numerical simulation methods were used to analyze and study the evolution mechanism of the beach.Based on the analysis results of beach erosion and retreat mechanism,targeted sandy shoreline restoration plans were proposed. The research results indicate that artificial sand replenishment can reshape the beach,and measures such as setting up sand barriers,offshore submerged breakwater,and underwater sandbars can achieve relative stability of the beach coastline,achieve dynamic equilibrium of static cape bays,and provide reference for similar sandy coastline restoration designs in the future.