The supplied water of the west route of Water Transferring Project from South to North of China is for industry, life and eco environment. Among these, water used for eco environment represents a great ratio. When the transferred water reaches 1.70×1010m³, the amount used for eco environment can be as high as 6.30×109msup>3 or 37.0% of the total. The benefits of the project on eco environment in water received area are analyzed. The analysis indicates that the project is the water resource guarantee for western China development. It can increase the runoff of the rivers in that region and improve the water environment, stop and control soil and water loss and land desertification, decrease natural disasters, improve the agricultural eco environment and local survival for the inhabitant, alleviate no water flow in the lower reaches of the Yellow river and solve related eco environment problems, restore the eco system and enhance environmental capacity and load bearing capabilities. From the sense of eco environment improvement, the west route of Water Transferring Project from South to North of China is a magnificent ecological construction project.