The problem of water resources shortage is an importent factor which constrains the development of agriculture economy so that the balance problem between the efficiency of water resources utilization and agriculture. The paper proposed to set up plan model of agriculture water resources based on the method of fuzzy credibility-constrained. The method realized the greatest agriculture benefit through regulating the balance problem between water demand and agriculture efficency.The established model improved the shortcomings of planning method in the past,and set up an irrigation systems under different credibility levels of λ value and different scenarios, which can provide important reference for decision-makers. The results show that the irrigation ratio of three categories in the irrigation system of a place of Urumqi has greater impact on the final sum of the profit gain.The credibility level λ is the important factor to weigh the benefits and costs. The study on the impact of confidence level λ on the model can provide more options to optimize water management for decision makers and improve the social, economic and environmental benefits of agricultural irrigation system.