For the case of vehicle impacting on bridge piers，a new anti-collision device made of aluminum foam for bridge piers is presented in this paper. The three-dimensional solid element models of piers with and without the anti-collision device are built by using the LS-DYNA software. The dynamic time-history responses of piers under vehicle impact are investigated. The impact force of the vehicle，the displacement and stress of the bridge piers in two situations are compared. The energy dissipation capacity of the anti-collision device and the vehicle damage severity are analyzed from the perspective of energy transmission. It is shown that the impact force，pier displacement and stress of the pier could be significantly reduced with the proposed anti-collision device.Most of the energy during the impact process is absorbed by the device. The aluminum foam anti-collision device can protect the pier and the vehicle at the same time. The research outcome can provide guidance for the future study in the field of vehicle and bridge collision problem and bridge piers anti-collision design.