PURPOSE: To improve the impact absorbing performance by setting the force against the backward movement of a wheel smaller than the force against the other directional movement by a wheel supporting outer subframe and a body side mounting inner subframe in an automobile suspension system.

CONSTITUTION: An outer subframe 1 is formed of a vertical pair of forked structural members 2, 4 and a vertical member 5, and a regulating means 8 consisting of a spring or the like is interposed between it and a chassis 9. A wheel 7 is mounted on an axle 6. A U-shaped sectional inner subframe 10 has front and rear bored flanges 12, 13 toward the vehicle outside to support the inside end part of the forked structural member 4 in such a manner as to be rotatable around the vehicle longitudinal horizontal axis. Further, it has upper subframes 16, 17 forming a triangle therewith to support the inside of the forked structural member 2 through short shafts 19, 20, respectively. And the inner subframe 10 is supported to the chassis 9 with fitting members 21, 22, 24. According to this structure, the cushioning performance can be improved.