Traditional mound breakwater structure in deeper waters brings cost rise sharply due to its large cross section.According to some research and engineering examples,It is known that rubble mound breakwater with pressure relieving inverted L breast wall can optimize the traditional breakwater pattern,guarantee the safety and meet the using requirements.Meanwhile,it can reduce the cost.Combining with an engineering case,this paper probes into the mound breakwater structure optimization design,which provides reference for similar projects.