To accurately evaluate the carrying capacity of water resources in Xinxiang City, a water resources carrying capacity assessment index system composed of “water resources-society-economy-ecology” was constructed, and TOPSIS was used to combine the entropy method and the analytic hierarchy process to assign weights. The water resources carrying capacity of Xinxiang City from 2006 to 2018 was comprehensively evaluated using this model, and then the evaluation results were analyzed by the obstacle degree model. The evaluation results showed that the water resources carrying capacity of Xinxiang City has been increasing year by year from 2006 to 2018. Although there were decreases in the span of time, the overall situation showed an improving trend; the obstacle degree results showed that the main obstacles hindering the development of Xinxiang City’s water resources carrying capacity were mainly the ecological and water resources dimensions. Eco-environmental water use rate was the principal obstacle factor hindering the improvement of water resources carrying capacity, water production modulus came the second, whereas water supply modulus, water use of the Yellow River and treatment rate of domestic sewage were the tertiary factors. In the future, more attention should be paid to the ecological environment protection and the improvement of the utilization efficiency of water use of the Yellow River for the development of Xinxiang City. At the same time, it is necessary to promote the development of water-saving industries and tertiary industries.