Twelve island counties of China are located scatteredly in four large seas including Huanghai.There exist some differences in economic level among twelve island counties because of their positions of sea area,the degree of abundance of resources of marine and land-islands, market mechanism and humanity states,island resources development dynamics and the effect of the position of their respective administrative divisions.From Gi-Ni coefficient based on per capita GDP of island counties and Lorenz curve,it also can be seen the differences are becoming smaller apparently.Seen from the industrial structure of island counties,there are different progressive course among them.According to characteristic value and distribution of island counties on the system of coordinates,we can identify different progressive stages of industrial structure and types of industrial structure.Island economy of China today is still resources-oriented economy,but in the aspect of resources exploitation and utilization,we have gradually changed the situation from merely taking utilization of marine organisms resources in domination to laying equal stress on the utilization of marine spatial resources,marine non-organisms resources,island-land land resources and marine organisms resources.Some industries which were developed on the land are starting to be shifted and extended so that the proportions of secondary and tertiary industries increased in the economic structure of island counties to a certain extent.