As an important part of coastal nuclear power plant,the design standard of marine structures is worth studying and discussing.According to the requirements of the regulation of nuclear power safety and related specification,we analyze the structural function of marine structure in coastal nuclear power plant,systematically classify the safety levels of various marine structures,clarify the contents to be considered in the design standard of marine structure for nuclear power plant,and summarize the principle for determining the design standard of marine structure.Combining with Lufeng nuclear power plant under construction in China,we determine the standard value of design parameter for this project,and summarize the idea and method of reasonably reducing the design standard for marine structures in nuclear power plants.It can provide references for the similar projects.