Abstract: For polymer foam cushion of automobile chair, a modeling method and process of nonlinear elastic-damping characteristics are analyzed. Firstly, a dynamic characteristic test of the polymer foam cushion is carried out. A mathematic model expression is determined according to the nonlinear dynamic characteristics of the cushion, and the model parameters are identified based on a series of experimental data. Thus, a nonlinear elastic-damping model of chair cushion is created, and a relationship of dynamic load vs. deforming displacement and velocity of the cushion is acquired. Meanwhile, an experimental measurement of pressure distribution of human body to seat cushion is carried out. According to the body pressure distribution, a distributed model of vertical nonlinear elastic-damping characteristics of chair cushion is derived, in which the angular vibration response characteristics of human body can further be simulated. Finally, a simulation analysis on dynamic response of the seat-occupant multi-body system is evaluated by taking advantage of the proposed dynamic model of the polymer foam cushion.