<p>Flooding poses a significant risk to urban metro networks, leading to station closures and service suspensions. By integrating the flood vulnerability of metro stations, this study evaluates the robustness of urban metro networks. Utilizing geographical, topological, and socio-economic data, the impact of flooding on the metro network is quantified. A composite index, which combines flood vulnerability with topological properties, is developed to evaluate the importance of individual stations under flood conditions. The Changsha metro network is analyzed as a case study, with simulations conducted to compare its performance in cascading and non-cascading failure scenarios. Three damage strategies—targeting stations based on degree centrality, flood vulnerability, and station importance—are applied to analyze network disruptions. Performance metrics, including the relative size of the largest connected subgraph (RS) and the network efficiency (NE), reveal varying degrees of network degradation under each damage strategy. The results show that stations such as Orange Isle Station and Xiangjiang Middle Road Station are highly susceptible to flooding. The network is most vulnerable to importance-based damage, with the removal of the top 6% of critical stations leading to a significant reduction in overall performance. These findings provide insights for enhancing urban metro network robustness, supporting station maintenance, and informing disaster prevention efforts.</p>