To provide a protective barrier which permits only a part needed only at the time when the transparency is lost due to degradation, secular change or the like to be replaced, and can unerringly absorb impact energy at the time of collision.

Transparent synthetic resin barrier plates 7-1 and 7-2 formed into the length from a main pole 1 to the main pole 1 are split into at least two upper and lower plates, and both ends are removably attached to the main poles 1 erected at a prescribed interval through forward and backward movable mounting brackets 3. Perforated shock absorbing members 35 having many perforations are provided between the barrier plates 7-1 and 7-2 split into upper and lower plates, and wires 43 which are given a tensile force by a tensile force applying means 45 along the barrier plates 7-1 and 7-2 and preventing waving are provided.