Vegetation and soil are two important components of the terrestrial ecosystems. There is to some extent an interaction between vegetation and soil systems and they influence each other. Therefore, exploring the coupling coordinative relationship between vegetation and soil could be the key to successful implementation of ecological restoration and reconstruction in the terrestrial ecosystems. The islands of the South Sea in China are located on the edge of the world's largest tropical-subtropical shelf, which are an inalienable part of China's territory. Due to clear boundaries and isolation from the land, islands are faced with problems such as strong habitat heterogeneity, lack of plant germplasm resources and fresh water, large evaporation, and so on. They are special and independent ecosystems which are more vulnerable to extreme climates or natural disasters such as typhoons, and become easily degraded but difficultly to be restored. This paper is based on the comprehensive investigation and systematic determination between vegetation and soil systems in the typical vegetation communities on five islands in the northern South Sea, China, i.e., Damiaodun Island, Weizhou Island, Dahan Sandun Island, Ganzhe Island, and Wuzhizhou Island. The two-level index system combined with 10 vegetation factors and 14 vegetation factors were established to determine the weight of each factor by the analytic hierarchy process, and then to build coupling models and coupling coordination models of vegetation and soil systems in the five islands. The results showed that the vegetation-soil coupling models and coupling coordination models in different islands were not completely corresponding. In addition, the comprehensive indexes of vegetation and soil were not completely consistent in each island. The vegetation effect of Ganzhe Island and the soil effect of Dahansandun Island were the best, respectively. The coupling coordinative status of vegetation and soil was good in the five islands in the northern of South Sea, China, which were in a state of primary or intermediate coordinated development. All the islands were in the synchronization type of vegetation and soil except Ganzhe Island. In general, due to islands far from land with relative small human interference, during the long-term succession of vegetation and soil, the coupling coordination between vegetation and soil systems in the northern islands of the South Sea of China was in a good status. Therefore, special attention should be paid to improve plant diversity, tending level, and soil management level during the process of vegetation restoration and ecological reconstruction in the northern islands of the South Sea of China.