To provide a guard cable which is constituted by laying a plurality of cables at intervals in a vertical direction of a support among the supports erected at regular intervals.

A rectangular steel pipe is used as the support 3; the supports 3 are disposed in such a manner that lateral surfaces face each other in an extension direction of a road, and erected by being insertably/extractably inserted into a hollow portion of a sleeve pipe 5 pre-buried in the ground; a slit 6, which is formed by opening an upper end and notching the upper end almost downward, is provided in a shape having one or more critical points and/or one or more inflection points in a vertical direction, in each of the upper portions of the two side surfaces of the supports 3; each of the slits is formed in a symmetrical shape in a view from one lateral direction; the cable 2 is laid between the supports 3 through the slit 6 of the support 3; and the vertical interval is maintained by a spacer 7 inserted into the support 3.