PURPOSE: To promptly exchange a post, by dividing in two the post of a protec tion fence for road and constituting it by the lower part of the post with a larger bending strength than the upper part thereof and further uniting the upper and lower parts by flanges.

CONSTITUTION: A protection post 1 for road is divided to the upper and lower parts to place the position 2 at a point as low as possible or to constitute it by the lower part 8 of the post with a larger bending strength than the upper part 3 and flanges 5, 6 are fitted at the bottom of the upper post and the top of the lower post are fastened by the combination 7 of male screws and female screws. As a result, damages of the post are mostly restricted in the upper part 3 and promptly recovered by the replacement of only the upper post 3.