Abstract: The purpose of this research is to probe into the dynamic responses of cable-stayed bridges to the attack of a conventionalweapon to provide an important reference for the feasibility studies of engineering protection and repair technology of importantbridges. A nonlinear finite elementprogram, LS-DYNA, wasused to simulate the dynamic responses ofcable-stayed bridgeswith differentstructural systems,i. e., suspension system, rigid-frame system and support system, to a long-rod projectile impactwhen bridge pylon is attacked. The effects of structural systems on the dynamic responseswere compared. The numerical results show that the local deformation in the region of collision is largest when bridge pylon is subjected to impact load parallel to the bridge axis, and the local deformation of the suspension system is least in the three systems. To a rigid-frame system, the dynamic plastic deformation of the intermediate column ofpylon under impact is larges,t and the dangerofbridge pylon fracture and the vibration responses of themain longitudinal girder aremostobvious.