At present, China's economy has shifted from a stage of rapid growth to a stage of high-quality development.The ocean is a strategic place for high-quality development, and the promotion of high-quality development of the marine economy is a fundamental requirement for determining the thinking on the development of the marine economy, formulating routes and implementing macro-control policies in the current and future periods.Based on the five new development concepts, it has constructed an evaluation index system for the high-quality development of the marine economy that includes the five dimensions of "innovation, coordination, greenness, development and sharing".For the panel data of marine economy of 11 coastal provinces from 2017 to 2021, the entropy weight TOPSIS model is applied to construct the evaluation index of high-quality development of marine economy,and conduct quantitative research and assessment analysis.The results show:(1)In 2017-2021, the level of high-quality development of China's regional marine economy as a whole fluctuated upward, and inter-regional differences in the first narrowing and then expanding trend.(2)There were significant differences in the level of high-quality development of the marine economy in the three major ocean economic zones during the study period.