Abstract: The Changjiang River Basin has established a comprehensive system that covers flood control, ecological environment preservation, and the efficient utilization of water resources.Though the initial outcomes in safeguarding the water ecological environment of the Changjiang River are emerging, the persisting water security issues that hinder high-quality economic and social development remain unresolved.A thorough analysis was conducted on current problems and causes in fields such as characteristics and control difficulties of flood and drought disasters in the Changjiang River Basin, water quality and heavy metal pollution, aquatic habitats and biodiversity, water shortage and water resources allocation, soil erosion and its control.We highlight the critical focal points and challenges of water security in the Changjiang River Basin, such as water disaster control, water quality improvement, water ecosystem restoration, water supply security, and soil and water conservation.To address these challenges, we propose strategic countermeasures and recommendations, such as enhancing the flood control system and optimizing the dispatching of water conservancy projects, optimizing the layout of industrial parks and river-along enterprises and manufacturing technological advancements, riparian ecological environment protection and conservation of biodiversity, ensuring water use safety during low water periods, strengthening water resources supervision and management, implementing soil and water loss zoning and classified control measures.These measures aim to provide water security assurance for the high-quality development of the Changjiang River Basin.