PURPOSE: To provide sufficient strength and elasticity to a pin, and to make it light and corrosion-resistant by a method wherein the pin for use in pinning method is made of fiber-reinforced plastics.

CONSTITUTION: A pin is formed by arranging reinforcement fibers such as carbon fibers, glass fibers or aramid fibers in a matrix resin composed of phenol resin, epoxy resin, unsaturated polyester resin, etc., in the axial direction of the pin so that the reinforcement fibers become 40-70vol.% in the matrix resin. Then, a groove 2 is cut spirally over the surface 1 of the pin, and thereby the pin made of fiber-reinforced plastics for use in pinning method is formed.