In power system dynamic simulation， it is difficult to give a true picture of the behavior law of security and stability control system due to the lacking of relative models. A general modeling method for security and stability control system is proposed， and the dynamic simulation calculation including security and stability control system models is also realized. With hierarchical structure and object-oriented modeling strategy， this method has the advantages of clear logic and convenient modeling. The new method can be applied to simulate cascading outages relating to actions of inverse-time relay and generator relay and zone 3 impedance relay caused by flow transferring. Meanwhile， it significantly reduces the computational costs. The simulation results reveal that the dynamic simulation program， including security and stability control system models， can represent more accurately the dynamic performance of electric power system after disturbance. It can be an effective tool to the large-scale power system electromechanical transient， medium-term and long-term course dynamic simulations， and to find the correct fault prevention measures for wide area blackout caused by cascading failures.