The invention discloses a UPFC-considered ATC calculation method of an electric power system including wind power. An ATC calculation optimization model including a UPFC equivalent power injection model is established, i.e. the ATC calculation optimization model is applied to the electric power system including wind power access, based on which the uncertainty of the wind power plant output is processed by using an IGDT, the ATC is calculated and the calculation example analysis result indicates that the robustness is high, the method has better IGDT than that of a probability method, the available power transmission capacity of the electric power system can be enhanced, the robustness of wind power fluctuation can be enhanced to a certain extent and the stability of the system can be enhanced so that the calculation method is enabled to have large advantages, have important meaning for calculation of the available power transmission capacity of the electric power system having uncertainty and have great application prospect.