The Guangdong-Hong Kong-Macao Greater Bay Area has a high level of urbanization，a dense population，and a developed economy. It is necessary to strengthen its water resources guarantee capacity to ensure its economic and social development and high-quality construction. The study found that with the exception of Huizhou，Zhaoqing and Jiangmen，the capacity of water resources in other cities was weak. The water supply in Shenzhen and other cities could not meet their economic and social development needs. The water resources in Shenzhen，Guangzhou，Dongguan，Foshan，and Zhuhai were developed and utilized. Tends to saturation. Shenzhen，Dongguan，and Zhongshan are all typical cities with rising water vulnerability and are extremely scarce. Although Foshan，Guangzhou and Zhuhai are cities with stable water resources fragility，they are transforming from mild water shortage cities to key water shortage cities. In summary，unlike other northern regions where water resources are in short supply，water resource constraints in the Guangdong-Hong Kong-Macao Greater Bay Area are mainly characterized by uneven spatial distribution，prominent supply-demand contradictions，serious regional resource water shortage problems，and regional typical water quality water shortages. The situation is relatively common，high water resource development and utilization，severe water resource security situation，frequent floods and flood disasters，and weak flood prevention and disaster resistance capabilities. Aiming at the reasons for population，industry，geography，and water resources development and utilization，the article puts forward some corresponding measures and suggestions on strengthening the water resources protection capacity of the Guangdong-Hong Kong-Macao Greater Bay Area，including strengthening the unified management of water resources management and water environment supervision in the Pearl River Basin Governance；speed up the construction of water resources allocation projects，and fundamentally alleviate the resource shortage constraints in the Greater Bay Area；increase waste water treatment and aquatic ecological restoration efforts，and actively promote the use of secondary water；strengthen demand-side and supply-side management，and improve And implement the most stringent water resources management system；accelerate the pace of industrial transformation and upgrading，improve the efficiency of water resources utilization；enhance the capacity of the Greater Bay Area to prevent floods and droughts and prevent environmental risks.