Abstract: In recent years, floods and waterlogging disasters have occurred frequently in the Guangdong-Hong Kong-Macao Greater Bay Area.Conducting comprehensive risk assessments is crucial for risk prevention in the Greater Bay Area.A research framework of "disaster causing factors, disaster prone factors, disaster bearing factors, and disaster resistance capacity" was constructed.Based on the combination weighting method of GIS and AHP-EWM, the risk characteristics of flood disasters in the Greater Bay Area were systematically evaluated.The results showed that:①Rainfall, development intensity (vegetation coverage and building density), and economic activity intensity were the main influencing factors of flood disasters, among which development intensity had a particularly significant impact on flood disaster risk; ②The Greater Bay Area has formed a composite spatial pattern of "high in the south and low in the north, river mouth polarization, and urban intensification"; ③Both sides of the the Pearl River Estuary are characterized by high potential risks and strong disaster resistance, and a high-risk continuous zone has been formed, which is caused by its rich water network resources, high-density development and construction, and high-intensity economic activities. Based on risk assessment, the study proposes the establishment of a multiscale, multi-dimensional, all-round, and intelligent flood disaster "monitoring, identification, warning response, recovery" full life cycle prevention and control and management system, which can effectively assist decision-making and reduce the impact and losses of flood disasters.