This paper analyzes the frictions in a real Inverted Pendulum System. The developed model, involving the addition Coulomb friction, is compared through real experiments with the models in which only the viscous friction is considered. Using the prediction error method, the model parameters including the moment of inertia and friction coefficients can be identified simultaneously. The numerical results show that the proposed model is able to provide the more precise description of the electromechanical device. © 2009 IEEE.