Since the 18th National Congress of the Communist Party of China, China has put ecological environment protection in a strategic position, and the water ecological environment in China has been notably improved. However, the water ecological environment in China still face various problems, such as eutrophication, pollution of drinking water sources, pollution of groundwater and coastal waters, new pollutants, and shortage of water for ecological use. In 2020 and 2021, the Chinese Academy of Engineering carried out the major consulting projects: “Research on Water Security Assurance Strategy for Ecological Civilization Construction”, “Strategic Research on the Coordinated Development of Water Balance and Land Space (Phase I)”, and “Assessment of the Implementation of the Law on Prevention and Control of Water Pollution”, which proposed targeted countermeasures and suggestions for the outstanding problems regarding water security in the process of ecological civilization construction in China, major water balance problems during the utilization and restoration of land space, and major problems regarding water pollution prevention and control. It is expected to provide support and references for the decision-making of relevant departments. (On the cover shows the ecological beauty of the Danjiangkou Reservoir of the South-to-North Water Diversion Project)