Based on the research of water resources and utilization situation in Hefei, the paper analyzed the utilization potential of water resources reasonably. By using the basic theory of water supply-demand balance, combining qualitative with quantitative, and according to the social economy development scale of Hefei in different level years, the paper predicted the supply and demand of water resources and analyzed the water resources carrying capacity.It objectively evaluated the water resources allocation in different level years so as to ensure that the development and utilization of water resources is within the allowable range of resources and environment carrying capacity. It made scientific plan,optimal allocation, high efficient utilization and saving protection for limited water resources from the macroscopic angle. Finally, the paper proposed some measures and suggestions for the security of water supply in Hefei so as to insure regional harmony and sustainable development.