The rotating inverted pendulum is a typical high-order,multi-variable and nonlinear complex system,and it is a classic model in the research and teaching of control theory.An accurate mathematical model is the premise of using a rotating inverted pendulum in research and teaching.However,it is usually difficult to establish a mathematical model that is consistent with the actual prototype due to the complexity of the rotating inverted pendulum.The mathematical model of the rotating inverted pendulum system was established by using the Lagrange equation,and then the parameters of the actual prototype were identified to determine the specific parameters of the model,thereby an accurate mathematical model of the rotating inverted pendulum was established.This method specifically shows how to build accurate mathematical models for practical electromechanical systems.On this basis,the model is simulated by using the S-function of MATLAB,which verifies the effectiveness of the method.