Abstract: In this paper, the mechanics model of vehicle vibration(include vehicle vertical vibration,vehicle longitudinal vibration and torsional vibration of the powertrain) was established. The nonlinear differential equations of vehicle vibration were linearized at the balance point and its eigenvalues were calculated to judge the stability of the vehicle vibration system. In addition, a critical stability parameter surface to show the stable area was drawn to provide a theory for supressing self-excited vibration.