Abstract: The South-to-North Water Diversion Western Route Project area includes fragile ecological areas.Mitigating the project's ecological impacts is one of the key concerns influencing the feasibility of the project.This article illustrates the need for research on the ecological impacts of water diversion in the Western Route Project.It identifies key scientific concerns related to the adaptive regulation of water diversion thresholds and disturbances for the new situation.This study developed a general research framework for assessing and addressing the ecological impacts of the Western Route Project, and proposes key research areas.They include investigating the coordinated evolution mechanism of water resources, water ecology, and economic society in the water source area and developing assessment methods and dynamic allocation techniques for ecological water demand in the water source area, water resource endowments and adjustable water thresholds under changing environments.It also includes ecological compensation mechanisms for water diversion, biological risk invasion analysis, and a comprehensive assessment and optimization of the water diversion impacts from a systematic perspective.The South-to-North Water Diversion Western Route Project must properly coordinate the potential conflicts between the water diversion projects and their ecological protection, adhering to the principle of ecological priority, to ensure that the comprehensive benefits are shared equally between the water source area and the water receiving area.