PURPOSE: To obtain a supporting structure of an instrument panel reinforcement which can prevent the bending of the instrument panel reinforcement, without incurring the increase of the weight of the panel reinforcement.

CONSTITUTION: A bracket 14 as installation means is fixed on a cowl 12. At the edge part on the opposite side to the body installation part 18 of the bracket 14, a semispherical projection part 28 is formed, and in the vicinity of the outer peripheral part of the projection part 28, the edge part 30A of an instrument panel reinforcement 30 is welded. Between the body installation part 18 of the bracket 14 and the projection part 28, a hole 32 as brittle par is drilled. The hole 32 is formed to a trapezoidal shape which is wide on the body installation part 18 side and narrow on the projection part 28 side, and the part between the body installation part 18 of the bracket 14 and the reinforcement 30 of the bracket 14 can be easily torsion-deformed.