In this study, we presented a model based on the Bouc-Wen-Baber-Noori (BWBN) method to describe the distorted hysteretic behavior of a magnetorheological (MR) damper. Dynamic performances of the self-made MR damper were measured with an Instron test machine. Experimental results indicated that the MR damper exhibited a force-lag phenomenon. The parameters of the BWBN model were identified with the MATLAB SIMULINK design and optimization toolbox. The comparison between the experimental results and modeling predictions demonstrated that the proposed model can well present the force-lag phenomenon.