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In the context of climate change, coastal flood risk is intensifying globally, particularly in China, where intricate coastlines and frequent tropical cyclones make storm surges a major concern. Despite local government's efforts to initiate coastal monitoring networks and qualitative risk guidelines, there remains a gap in detailed and efficient quantitative assessments for combinations of multiple sea‐level components. To address this, we develop the Tropical Cyclone Storm Surge‐based Flood Risk Assessment under Combined Scenarios (TCSoS‐FRACS). This framework integrates impacts of storm surges, high tides, and sea‐level rise using a hybrid of statistical and dynamic models to balance reliability and efficiency. By combining hazard, exposure, and vulnerability, it incorporates economic and demographic factors for a deeper understanding of risk composition. Applying TCSoS‐FRACS to Hainan Island reveals that the combined effects of storm surges, high tides, and sea‐level rise significantly amplify local coastal flood risk, increasing economic losses to 4.27–5.90 times and affected populations to 4.96–6.23 times. Additionally, transitioning from Fossil‐fueled Development (SSP5‐8.5) to Sustainability (SSP1‐1.9) can reduce the risk increase by approximately half. The equivalence in flood hazard between current high tides and future sea level under a sustainable scenario boosts confidence in climate change adaptation efforts. However, coastal cities with low hazard but high exposure need heightened vigilance in flood defense, as future risk could escalate sharply. Our study provides new insights into coastal flood risk on Hainan Island and other regions with similar profiles, offering a transferable and efficient tool for disaster risk management and aiding in regional sustainable development. Plain Language Summary: Climate change is intensifying coastal flood risk worldwide. We developed TCSoS‐FRACS, a framework that assesses flood risk from storm surges, high tides, and sea‐level rise, using a combination of dynamic and statistical models. This framework evaluates hazard, exposure, and vulnerability to predict affected populations and economic losses across various land uses. When applied to Hainan Island, it shows that the combination of storm surges, high tides, and rising sea levels significantly increases flood risk. However, transitioning from a Fossil‐fueled Development Path to a Sustainability Path can reduce this increased risk almost by half. The study also finds that, on Hainan Island, current high tide hazards may be comparable to future sea‐level rise hazards under a sustainable scenario, boosting confidence in adaptation efforts. Coastal cities with low hazard but high exposure need greater vigilance, as their future flood risk could rise sharply. Our research offers valuable insights and tools for managing coastal flood risk in Hainan Island and similar regions, supporting sustainable development and effective disaster management. Key Points: Design a flood risk framework for TC storm surges combined with high tides and sea‐level rise using hybrid dynamic and statistical modelsEquivalence in flood between current high tides and future sea level under a sustainable scenario boosts confidence in adaptation effortsCoastal cities with low hazard but high exposure need heightened vigilance in flood defense as future risk could dramatically escalate [ABSTRACT FROM AUTHOR]