To evaluate eco-environmental carrying capacity, the core task is to estimate whether the intensity of human activity is within the threshold value of the eco-environmental carrying capacity. However, both the intensity of activity and the threshold value are difficult to measure correctly. In an attempt to solve the problem of evaluating eco-environmental carrying capacity, from the viewpoint of eco-environment system operating status, we present a new method of eco-environmental carrying capacity evaluation, called the "Eco-environment Index dynamic evaluation method," which is based on the ecological balance theory and the ecological stability principle. The processes adopted using this method are as follows. The first is providing an evaluation criterion of eco-environmental carrying status, that is, whether the eco-environment system is operating well. The second is calculating values of the eco-environment index (EI) in different years using an existing EI model. The third is judging the eco-environment system operating status based on the change trend of EI by regression analysis. Using these steps, eco-environmental carrying capacity can be evaluated. The evaluating process is demonstrated by using the case study of Henan Province, which yielded the following results. (1) Although eco-environmental carrying capacity evaluation is different from the EI, it can be performed by regression analysis of the EI. (2) This method, by following the strict definition of carrying capacity and avoiding the difficulty of estimating the intensity of activity and threshold value, provides a new way of thinking and a new approach to eco-environmental carrying capacity evaluation. Moreover, it is concise, easy to perform, and of clear significance. (3) Attention should be paid that the eco-environment quality cannot reflect the carrying status, for the region with a high eco-environment quality can be overloaded such as Xinyang, and the opposite case can be also exist such as Puyang and Anyang in Henan.