In recent years, China's economic development has maintained rapid growth, and the demand for water resources is also increasing day by day. However, shortage of water resources and inefficient use of water have become an obstacle to the sustainable development of China's social economy. The research on spatial correlation network characteristics of China's water resources green efficiency can lay a foundation for optimizing the overall spatial pattern of China's water resources green efficiency and realizing the cross-regional synergistic promotion of it. Therefore, from the perspective of Group Frontier, this paper divides 31 provincial-level regions in China into three groups: eastern, central and western. It uses SBM model to measure the green efficiency of water resources in different areas, and uses VAR Granger causality test to transform "attribute data" of water resources green efficiency into "relational data". On this basis, the spatial correlation network characteristics of water resources green efficiency in China are studied by means of social network analysis. The results show that the regional differences in China's water resources green efficiency are significant, and the overall performance is characterized by central > eastern > western region. The spatial correlation of the water resources green efficiency of between provinces of China presents a more complex network structure, all regions are in the spatial correlation network of water resources green efficiency, and the network overall has the strong stability. The individual characteristics show that the eastern region is dominated by spillover effect, which plays a role of "engine" in the optimization of national water resources green efficiency, while the western region is dominated by the spillover from other regions, which is in the edge position in the network structure. Block model analysis shows that there are 10 provinces in "net overflow" plate such as Beijing and Tianjin, and 8 in "net benefit" plate such as Qinghai and Xinjiang, and 6 provinces in "two-way overflow" plate such as Hebei and Chongqing, and 7 in "brokers" such as Henan and Shaanxi. The results provide suggestions for the improvement of water resources green efficiency and the coordinated development in different regions of China.