In order to guide the comprehensive planning and management of water resources in Hefei City scientifically, thirteen indicators were selected from the support, pressure and control subsystems based on the comprehensive analysis of the relationship between water resources carrying capacity and water resources-social economy-the ecological environment system. The evaluation index system of water resources carrying capacity of Hefei City was established, and the water resources carrying capacity of Hefei City from 2011 to 2016 was evaluated comprehensively using the connection number evaluation model. The results showed that the evaluation level of Hefei City were grade three from 2011 to 2015 and grade two in 2016. The overall situation was grim and the carrying capacity was poor, but it had improved and the development trend was good. Based on the theory of subtraction based set pair potential, the main factors affecting the carrying capacity of water resources in Hefei City were determined as per capita water resources, water production modulus, vegetation coverage, population density, utilization rate of water resources development and ecological water consumption rate.