Climate change has significantly increased the frequency and intensity of urban flooding, making resilient urban planning a critical necessity. This study aims to evaluate urban flood risk in Küçükkuyu (Çanakkale, Türkiye) within the framework of ecosystem services and climate adaptation strategies. The InVEST Urban Flood Risk Mitigation model was used to analyze surface runoff, runoff retention, and flood volume based on land use/land cover, soil groups, and topographic characteristics. Spatial analyses were conducted using ArcGIS and QGIS, incorporating parameters such as Curve Number (CN), rainfall depth, and infiltration capacity. The results indicate that impermeable urban areas, particularly coastal zones, exhibit low runoff retention capacity and higher flood risk. The runoff retention index was calculated as 0.20, while retained runoff volume and flood volume were determined as 83 m³ and 90 m³, respectively. These findings reveal that approximately 20% of precipitation converts into surface runoff, increasing flood vulnerability. The study highlights the importance of integrating nature-based solutions such as green infrastructure and sponge city approaches into urban planning. Increasing permeable surfaces and establishing ecological buffer zones can significantly reduce flood risks and enhance urban resilience.