The porous honeycomb is widely used in the field of impact energy absorption due to its high porosity and low density. However, traditional honeycomb pedestals are mainly studied for the influence of the increase or decrease of uniform parameters on the impact isolation performance, and are prone to stress concentration, low in-plane stiffness and poor bearing capacity. Therefore, a cylindrical honeycomb pedestal is proposed, and its anti-deformation ability is analyzed. Through multiple sets of comparative simulations, the influence of the change of honeycomb core cell parameters on its impact isolation performance is discussed. On the premise of ensuring the mass and volume of the pedestals unchanged, honeycomb layers with positive thickness gradient, inverse thickness gradient, positive angle gradient and inverse angle gradient were designed with cell wall thickness and concave angle as independent variables, respectively. The effects of layered gradient design and gradient variation on the impact isolation performance of the pedestals were discussed. The results show that, on the one hand, the cylindrical honeycomb pedestal has higher specific stiffness and stronger bearing capacity than the regular square pedestal; on the other hand, the thinner the cell wall thickness, the greater the absolute value of the concave angle of the cell, and the better the impact isolation performance of the pedestal. The design of the thickness gradient has improved the impact isolation performance compared with the uniform parameter design. The positive thickness gradient design has the best effect, and the angle gradient design has no obvious effect on the impact isolation performance. At the same time, the greater the gradient change, the more significant the effect.