PURPOSE: To increase the absorption energy of a round board protector by providing the protector with a means for restricting the compression deformation by limiting the expansion deformation induced attendant on the progress of, and in the perpendicular direction to, the compression deformation.

CONSTITUTION: A round board protector 1 consists of a cylindrical body of rubber or rubber-like elastic material and receives the board load in the direction intersecting the axis shaftline of the cylindrical body. The protector 1 is provided with a means for restricting the compression deformation by limiting the expansion deformation induced attendant on the progress of, and in the perpendicular direction to, the compression deformation. The means may be a seat 3 fixed to the quay 4 by bolts or the like or may be a groove 6 formed in the quay 4. The means may further be a framework 7 comprising two rods 9 provided above and below the protector 1 and two rods 8 passe through the inner hole of the protector 1 for supporting the protector 1.