To provide a protective fence support satisfying the requirements of a safety standard, without having to renew the foundation.

A column section 23 is formed in a flat rectangular shape, having a cross section larger in the lateral direction than in the longitudinal direction. Since the column section 23 is formed in a hollow flat shape, the strength of the column section 23 is increased with respect to a load from the front plate 22 side. A front plate 22 comprises bent sections 26, 27. Hence, the bent sections 26, 27 of the front plate 22 are deformed before the deformation of the column section 23, and the load applied from the front plate 22 side thereto is relieved. Since the load from the front plate 22 side is absorbed due to the bending of the front plate 22, the load applied to a base section 103 is relieved. Since the load applied to the base section 103 is relieved, increase in the strength of the foundation 16 is not requested; and the protective fence satisfying the requirements of the safety standard can be installed, without renewing the foundation 16.