Abstract: Mangroves thriving in tropical and subtropical coastal intertidal zones, are one of the most climate-sensitive ecosystems. Climate change has profoundly impacted the survival and distribution patterns of global mangroves. This study applies the mangrove assessment index system, which is based on the comprehensive risk theory for climate change of Intergovernmental Panel on Climate Change (IPCC), and uses literature review, on-site supplementary survey data, remote sensing images, and model simulations, to evaluate the comprehensive risk of mangrove posed by climate change in the Zhanjiang Mangrove National Nature Reserve in Guangdong Province under low (RCP2.6), medium (RCP4.5), and high (RCP8.5) greenhouse gas emission scenarios for 2030, 2050, and 2100, respectively. Additionally, adaptive strategies to enhance climate resilience in mangrove ecosystems are proposed. Results show that firstly, under all RCP scenarios, the hazard intensity caused by gradual sea level rise combined with abrupt tropical cyclones increases over time with higher greenhouse gas emission concentration, peaking in the southern Leizhou Peninsula by 2100. Secondly, the areas with high exposure and vulnerability of mangrove forests within the protected area are the Qishui Bay, Haikang Port, and Liusha Port areas. Thirdly, comparative risk levels of mangroves from high to low during the same period across scenarios can be listed in order of RCP8.5, RCP4.5, RCP2.6. Under the RCP 8.5 scenario, by 2100, mangroves with a comprehensive risk level of high or very high will account for 91.54% of the total area of mangroves in Zhanjiang. Fourthly, sea level rise may inundate approximately 12.34% (RCP2.6), 22.67% (RCP4.5), and 26.87% (RCP8.5) of mangroves by 2100. Tailored conservation and restoration measures—such as constructing biological revetments, enhancing sediment retention, and replanting native species—are recommended to improve mangrove climate resilience, offering scientific insights for climate risk management.