The condition of water resources is the important guarantee and prerequisite of city economic and social development and ecological environment construction. Xi'an is a city short of water resources and has 23.49 billion m3 volume of water resource at average years. Xi'an is becoming an international metropolis full of historical and cultural characteristics. This paper analyzed the water use situation and supply capacity of Xi'an.Combined with urban water demand prediction, water project planning, and prediction of available water supply, it calculated the balance result of water resources in 2015, 2020, 2030, and put forward related measures to ensure water resources balance of supply and demand. The study has very important theoretical and practical value for economic and social development, high-effectively use and protection of water resources in Xi'an.