Abstract: The offshore area is a sensitive area of land-sea interaction. Due to the combined influence of natural and human activities, the sedimentary dynamic environment is more complex. The seabed surface is the key interface for the interaction between water and seabed, and the erosion characteristics of surface sediments are important factors affecting the evolution of seabed erosion and deposition. Based on the surface sediment samples of 91 stations and 10 undisturbed intubation samples in the southern sea area of Caofeidian in October 2021, the spatial distribution characteristics of critical erosion shear stress and erosion rate of surface sediments in the study area were analyzed by particle size experiment and indoor U-GEMS micro-erosion experiment. Combined with the numerical simulation results of tidal current, the erosion characteristics of surface sediments in the study area under the action of tidal current were discussed. The results show that the critical erosion shear stress of surface sediments in the area around the Caofeidian head is larger, and the critical erosion shear stress in the southern part of the study area is relatively small. The critical erosion shear stress of surface sediments is between 0.3-0.6 N/m2. The erosion rate increases linearly with the increase of shear stress, and the maximum erosion rate is 0.059 g m⁻² s⁻¹. The erosion characteristics of surface sediments in the study area are affected by tidal current and the erodibility of surface sediments. The research results are helpful to enrich the theoretical research results of offshore erosion and deposition evolution from the aspects of sediment erosion characteristics, and have certain guiding significance for offshore engineering construction and coastal protection.