In order to improve the shock resistance of shipborne equipment, the finite element model is constructed by the spring gap unit in ANSYS. The influence of the stiffness parameters of the restrictor on the shock resistance of the isolation system is analyzed by simulation calculation. The causes of the secondary impact are revealed and reasonable suggestions are given. The results show that: the relative displacement response decreases and the acceleration response increases rapidly of the isolated equipment with the increase of the stiffness ratio, and both of them are negatively correlated under any installation clearance;and the secondary impact is not affected by the stiffness of the traditional restrictors, and can be improved effectively by rationally selecting the restrictor parameters or designing a new displacementrestrict structure with large damp, thereby improving the impact resistance of the shipborne equipment.