Abstract: Statically indeterminate vibration isolation system is usually applied in ships. This study established a model of vibration isolation system in which four isolators were mounted on a flexible shipboard base. The dynamic control equations of statically indeterminate vibration isolation system were then obtained, while the isolators were represented as continuous beams, and the equipment as a rigid body. Power flow of the system was analyzed by the Matlab program. The results showed that the isolator of beam model led to a remarkable reduction in power flow, and that the internal resonance of these isolators had significant effects on the power flow of the system. Additionally, main design parameters of these isolators were discussed and the conclusions useful for engineering design were gained.