As ports and berths move deeper into the ocean,the problems of high cost and poor water permeability of traditional physical breakwaters become increasingly prominent.Combining the requirements of water permeability and wave dissipation in ports with large tidal range,a wave dissipation structure combining submerged breakwaters and baffle-type permeable breakwaters is proposed to achieve both high and low water level wave dissipation efficiency.There have been studies on the interaction between waves and individual submerged breakwaters or baffle-type permeable breakwaters,but there has been no precedent for their combined use at home and abroad,and there is a relative lack of research in this area.Through physical model experiments,this paper first studies the changes in energy spectrum caused by nonlinear effects when waves pass through submerged breakwater,and compares the wave dissipation performance of individual submerged breakwater,individual baffle-type permeable breakwaters,and combined breakwaters to further verify the rationality of the combined breakwater.Then,the wave dissipation characteristics of submerged breakwaters and baffle-type permeable breakwaters under different conditions are studied,and suggestions for selecting the spacing of combined breakwaters are proposed based on numerical calculations.The relevant conclusions can provide a basis for the design and application of such projects.