With the popularization of electric vehicles, the impact of electric vehicle charging is becoming prominent for power grids, and disorderly charging of largescale electric vehicles also have severe negative influences on the safety and reliability of the power grid and economic dispatch. On this background, considering the behavior characteristics of electric vehicle users, the economic dispatch of power systems is studied. Firstly, on the basis of the measured data, the uncertainty of electric vehicle charging is considered and the charging start time and duration are analyzed to obtain the time distribution of electric vehicle charging load. Secondly, the minimum sum of the coal consumption cost and the valve point effect cost of the system is taken as the objective function, and the penalty function method is applied to add function constraints. An economic dispatch model of power system is then established with the impacts of electric vehicle charging in consideration. Finally, the different charging behaviors of electric vehicles are simulated with cuckoo search algorithms respectively to verify the correctness of the proposed model, and the effects of different electric vehicles charging behaviors are analyzed for power systems.