Sandwich structure is an ideal lightweight structural material to resist explosion impact and ballistic penetration. First, the high-velocity impact response of double-layer K-cor sandwich structure is studied based on the first-stage light gas gun experiment. Then, the high-speed impact is simulated with the finite element model of double-layer K-cor sandwich structure. Besides, the energy absorption and failure modes during the impact are analyzed. Finally, the impact of changing structure on the high-velocity impact performance is discussed. The results show that the double-layer K-cor sandwich structure increases the ballistic limit speed by 8.3% compared to the sIngle-layer structure. The simulation results is agrees with the experimental values. The double-layer structure provides more interfaces for the system to increase energy absorption mechanism during the impact process. The increase of Z-pin implant density significantlyenhances the high-velocity impact performance of the K-cor structure.