Wetlands deliver multifunctional benefits to human settlements by supporting biodiversity habitats, flood regulation, and cultural services via cultural infrastructure synergy, addressing production-living-ecological (PLE) spatial demands. However, due to the lack of effective methods for identifying the functional differences of corridors in wetland networks, blind protection and utilization of wetlands may undermine the livability and sustainability of the habitat. Employing symbiotic system theory, this research focuses on Putian City's urban core within the Mulan River Basin and integrates three core human settlement needs—flood prevention, cultural tourism, and ecological conservation—into the development framework of wetland corridors. We propose a method for constructing a multifunctional "human settlement-wetland" symbiotic network. This approach includes morphological spatial pattern analysis (MSPA), landscape connectivity indices, integrating maximum entropy modeling (MaxEnt), minimum cumulative resistance (MCR) analysis, and hydrological simulations. Additionally, the spatial distribution of flood inundation risks, cultural landscape density, and biodiversity are transformed into functional resistance factors to extract potential functional wetland corridors and optimize wetland network structures. The results indicate that: (1) Land use type dominates wetland formation (86.9% contribution rate), surpassing climatic and topographic drivers. (2) In the Putian urban area, 32 wetland ecological sources were identified, and 39 potential flood regulation corridors, 54 cultural waterfront corridors, and 40 ecological wetland corridors were extracted. Among these, corridors with three functional types accounted for 56%, and those with two functional types accounted for 15%. (3) A three-level wetland network structure was established in the study area, with the first-level wetland network forming a "three vertical and three horizontal" spatial pattern. This study establishes a scientific foundation for multifunctional spatial zoning and blue-green infrastructure optimization, design, and management of urban wetlands and waterfront areas.