Abstract: Maintaining river-lake water system connectivity is the basic condition for the fluxion of material flow, energy flow, information flow and species flow in the basin and the quantitative evaluation of water system connectivity is very important. Taking the Sheshui River-Liujiaji River-Shangxida River area in Dawu County, Hubei Province as an example, this paper uses the theory of graph theory, the connectivity index and multiple centrality assessment model to analyze water network connectivity. The results showed that: (1) The graph theory index measures the connection characteristics of the water network as a whole, and the complexity of the water network in the study area is general; (2) The important degree of connectivity of each river chain are measured by the water network connectivity index, and the river chain with long length or in the artery is of great importance to the overall connection characteristics of water network; (3) The spatial centrality analysis of the water network can reveal the importance of different aspects of confluences or river chains. The centrality values of the isolated small water components are large. Closeness centrality analysis helps to discover the main trunk water system. Betweenness centrality analysis helps to find the confluences or river chains that are mainly connected in the water system. Straightness centrality helps to find the more tortuous river chains in the water network. The research results improve the evaluation of water system connectivity and have a certain reference value for water system connectivity engineering design and river health management.