Abstract: The perforated caisson structure has a good wave-dissipating effect due to the strong disturbance of the perforated front wall and the wave-dissipating chambers. Based on the physical modelling tests of perforated caisson in the Lanshan Port Terminal of the Rizhao Port, the wave dissipation effects and hydrodynamic characteristics of the perforated caissons with different hole-opening positions are studied and the reflection coefficients and the overtopping of different perforated caisson schemes are analyzed. The results show that the water level has a greater influence on the reflection coefficient and the scheme with higher hole-opening position has a better wave dissipation effect and a small overtopping. For conducting the hydrodynamic test the scheme that can make both the reflection coefficient and the overtopping small is chosen. The results demonstrate that the floating support force corresponding to the maximum horizontal force is about 60% of the maximum buoyancy force, while the horizontal force corresponding to the maximum floating support force is about 75% of the maximum horizontal force. The action of waves on perforated caisson is mainly concentrated on the wave-facing side of the outer wall, and the internal structure of the caisson is subjected to very little wave force. The wave force in the second wave-dissipating chamber is less than that in the first chamber.