Abstract: Due to the influence of human activities, the original water-sediment balance in the southern coastal area of Xiang’an, Xiamen has been disrupted, triggering a series of problems such as coastal siltation, weakened nearshore hydrodynamic conditions and beach mudification. By selecting the areas of the middle and eastern segments on the west side of the northern bank of the Dadeng Bridge as the study area, the key technologies for multi-parameter collaborative optimization in the restoration of muddy coastal beaches are studied. The evaluation of dynamic geomorphological suitability carried out by combining historical nautical charts and field measured data reveals that the annual average significant wave height in the study area is merely 0.1-0.3 m, indicating that auxiliary nearshore dredging work is required for improving hydrodynamic conditions. By focusing on the following three core parameters, namely the layout of sand-retaining dikes, the elevation of dredging bottom and the elevation of beach berm, three schemes are designed for the layout of beach restoration. The numerical simulations of the 10-year long-term evolution of coastal beaches and the extreme storms occurring once every 50 years are carried out by using models of SWAN, NEMOS and Xbeach, and the alongshore sediment transport, the shoreline erosion-siltation and the mudification inhibition effects of different schemes are quantitatively compared. The results indicate that Layout 3 of the three layout schemes can achieve the optimal comprehensive performance. By this layout, the elevation of beach berm can be optimized to 3.8-4.3 m and the length of sand-retaining dikes can be reduced by 18 m. After 10 years of restoration, the maximum erosion and siltation of shoreline in the middle segment area will be 25 m and 5 m respectively, while those in the eastern segment area will be less than 20 m and 3 m respectively. The annual average total beach erosion-siltation volume will be controlled within 9 000 m³ and in the 5th year of restoration the shoreline can reach a dynamic equilibrium. After dredging to a unified bottom elevation of −4.2 m, the tidal prism and nearshore wave height in the sea area will be increased significantly and the elevation of the sand-mud boundary will be lowered from the current 0.2 m down to −0.8 m, thus restraining effectively the trend of mudification. Under the extreme storm conditions occurring once every 50 years, the outer edge of the beach berm will retreat only by approximately 1 m after continuous action of waves on beach for 12 h, and the sediment transported laterally by storms can naturally back-silt during the periods of normal waves, indicating that the overall beach stability is controllable. This study can provide a quantitative technical basis and practical reference for similar sandy coastal beach restoration projects in China.