Abstract: The dynamic response and structural integrity of a typical spent fuel storage building of High Temperature Gas-cooled Reactor (HTGR) subjected to the impact of a twin-engine commercial aircraft were investigated. The effect of structural characteristics on the damage during the impact was discussed. Finite element models of the spent fuel storage building and the aircraft were established respectively. The impact process was simulated by an integral missile-target interaction analysis. The damage of the spent fuel storage building was evaluated according to IAEA and NRC standards. According to the results, acceptable local damage is observed in the areas corresponding to the impact of fuselage and engines. The walls of spent fuel storage silo play an important role in improving the resistant capability of structures against aircraft impact. In addition, the shape of the structure has a strong effect on the damage during an aircraft impact. Cylindrical shells show significant advantages in the resistant capacity against aircraft impact compared with square-shaped structures, which provides one of the optimization directions for structural design of nuclear power plant.