The parameter vibration is a hot topic for nonlinear vibration. Some results of its study have been used in aerospace, machining technology, motor vibration and many other fields, and the sport that people play on the swing is a classic one. In this paper, by creating the model of standard human body and swing, a biomechanical compound pendulum consisting of nine bodies and relevant force elements consisting of springs and dampers are regarded, then the movement is simulated in ADAMS. The time history of the swinging angle of the system is measured and the trace of the mass center is also displayed. Furthermore, in order to examine the stability of the system, the phase portraits are provided, and the stable diagram is obtained under different values of relevant parameters.