The development process of research on the water resources carrying capacity in China is systematically summarized, and it can be divided into five stages: the creation of conception, the preliminary study, the gradual improvement, the difficult development, and the innovation era. On the basis of comparison of research methods, the calculation methods of water resources carrying capacity can be divided into three categories: the empirical formula method, comprehensive evaluation method, and system analysis method. The control objective inversion model(COIM)based on simulation and optimization and its applications are introduced. It is pointed out that research on the water resources carrying capacity in the future focuses on: using the empirical formula method to calculate the national water resources carrying capacity and system analysis method for detailed calculation; constructing the calculation model of water resources carrying capacity and forewarning system platform; studying the dynamic carrying capacity of water resources under the changing environment; and considering the current achievements of water resources regulation and the balance development of water resources and economic society.