Abstract: The urging demands of water resource and deteriorating water conditions have become a serious impediment for China's economic development. Therefore it is very important to optimize the allocation of water resources to ensure its sustainable utilization. In order to solve the problem of uneven distribution among different provinces in 2025, an empirical study was conducted and an effective solution was proposed. Basing on time series model, the reserves and consumption of water resource in several provinces were forecasted. Then using cost-effectiveness model, the cost and effectiveness among three existing methods were compared, and the most effective strategy was recommended.