The invention discloses a symmetric fault transient stability analysis and control method in consideration of saturation characteristic of a virtual synchronous machine. Currently, a researching method which is related with transient stability of a virtual synchronous machine on the condition of large interference is not suitable for the symmetric shortcircuit fault of a power grid. According to the method of the invention, through establishing a system equivalent model before the symmetric fault of the power grid, in the symmetric fault of the power grid and after the symmetric fault of the power grid, through analyzing a transient stability mechanism and an instability process on the condition that the saturation characteristic of the virtual synchronous machine is considered, a fact that a main influence factor for transient stability of the system is power angle magnitude is obtained. Based on the fact, a corresponding measure is presented, thereby effectively suppressing transientenergy and improving transient stability of the system.