PURPOSE: To lessen the difference between initial reaction and average load while improving the strength of the frame member as an energy absorbing member, by arranging a pipe within a frame consisting of upper and under walls and both sidewalls.

CONSTITUTION: A frame member 2 is fixed in longitudinal direction of the car body 1. The frame member 2 is made integrally by extrusion working of aluminum material, or the like into a closed section which has an upper wall 3, a lower wall 4 parallel with this, both parallel sidewalls 5 and 6 coupling them at both their ends, a circular wall 7 arranged in the hollow part consisting of the upper and lower walls 3 and 4 and both sidewalls 5 and 6, and each intermediate wall 8-11 coupling the upper walls 3 and 4 and both sidewalls 5 and 6 with the circular wall 7. If load adds to the body by the collision of a vehicle, the load adds to the front of the frame 2 being a front side member, and the circular wall 7 seeks to cause buckling deformation. At this time, the load is dispersed to the upper and lower walls 3 and 4 and both sidewalls 5 and 6 through each intermediate wall 8-11, whereby stable crash deformation occurs on the whole.