The article used general equilibrium model to analyze the change of gross domestic product and industry output affected by water resources policies in Beijing City by using GEMPACK soft tool.The article researches on rules of water supply and demand,evaluating water resources,building water resources input and output table,establishing water computable general equilibrium model and stimulating water policy.The stimulation gives a scenario that increases water price by 10%.The result shows the following aspects.First,water resources policy infects gross domestic product and industry output in different ways.There are different behaviors in different industries as to the water policy. Agriculture industry has the same tendency as water price change and it has more sensitive to water quantity than to water price.For basic energy industries such as oil and chemistry and gas,they show diversity tendency.As to some high water consumer industry such as paper and textile etc.,water resource economic policy can infect them greatly and can promote them to accomplish more water-saving technology.Waste water and construction and service industries show the same tendency as to water policy.Second,government should pay more attention to water resource policy by macro economic administration.The simulation also shows that the output and supply and consumer price change more than expect as to water policy in a free market economic in water industry.So as to a government policy maker,one should be more carefully and prepare suitable forecast and plan to water policy and its negative impact. The article used general equilibrium model to analyze the change of gross domestic product and industry output affected by water resources policies in Beijing City by using GEMPACK soft tool. The article researches on rules of water supply and demand, evaluating water resources, building water resources input and output table, establishing water computable general equilibrium model and stimulating water policy. The stimulation gives a scenario that increases water price by 10%. The result shows the following aspects. First, water resources policy infects gross domestic product and industry output in different ways .There are different behaviors in different industries as to the water policy. Agriculture industry has the same tendency as water price change and it more sensitive to water quantity than to water price. For basic energy industries such as oil and chemistry and gas, they show diversity tendency. As to some high water consumer industry such as paper and textile etc., water resource ec onomic policy can infect them greatly and can promote them to accomplish more water-saving technology. Waste water and construction and service industries show the same tendency as to water policy .Second, government should pay more attention to water resource policy by macro economic administration. The simulation also shows that the output and supply and consumer price change more than expect to to water policy. A as to a government policy maker, one should be more carefully and prepare suitable forecast and plan to water. policy and its negative impact.