To provide an impact absorber absorbing the rectilinear energy of a vehicle traction apparatus traveling at high speed more largely than the conventional one.

Multiple stages of a plurality of metal cylinder bodies 22 are so provided that plates 23 and 24 with their axes facing to the advancing direction (impact absorbing direction) face to this advancing direction, and a top plate 25 is arranged in the forefront end so as to absorb the impact in collision acting on the vehicle traction apparatus 3 by an axial compression plastic deformation of the cylinder bodies 22. The ends of the respective cylinder bodies 22 are fixed to the plates 23, 24 and 25 by fitting. The diameter and the height of the whole of the cylinder bodies 22 and the impact absorber 21 are so decided as not to cause buckling by the load F.