A fastening pin to be driven into a rigid member, the fastening pin comprising: an enlarged head part ; and a shaft part , wherein the shaft part includes: a large diameter section formed below the enlarged head part ; a middle shaft section formed below the large diameter section ; and a small diameter section extending from the middle shaft section to a leading end of the fastening pin (A), wherein the large diameter section includes a round portion formed below the enlarged head part and a taper portion formed between the round portion and the middle shaft section , and a diameter of the large diameter section at a side of the enlarged head part is larger than a diameter of the large diameter section at a side of the middle shaft section , wherein the middle shaft section has a uniform diameter from a side of the large diameter section to a side of the small diameter section , and wherein a side of a leading end of the small diameter section has a bullet shape, characterized in that the small diameter section includes: a lower middle shaft portion having a uniform diameter which is smaller than a diameter of the middle shaft section ; a lower taper portion provided between the lower middle shaft portion and the middle shaft section ; and a leading end portion provided below the lower middle shaft portion and formed in the bullet shape, and wherein a taper angle (θ1) of the taper portion is within a range from 2 to 5 degree. an enlarged head part ; and a shaft part , wherein the shaft part includes: a large diameter section formed below the enlarged head part ; a middle shaft section formed below the large diameter section ; and a small diameter section extending from the middle shaft section to a leading end of the fastening pin (A), a large diameter section formed below the enlarged head part ; a middle shaft section formed below the large diameter section ; and a small diameter section extending from the middle shaft section to a leading end of the fastening pin (A), wherein the large diameter section includes a round portion formed below the enlarged head part and a taper portion formed between the round portion and the middle shaft section , and a diameter of the large diameter section at a side of the enlarged head part is larger than a diameter of the large diameter section at a side of the middle shaft section , wherein the middle shaft section has a uniform diameter from a side of the large diameter section to a side of the small diameter section , and wherein a side of a leading end of the small diameter section has a bullet shape, characterized in that the small diameter section includes: a lower middle shaft portion having a uniform diameter which is smaller than a diameter of the middle shaft section ; a lower taper portion provided between the lower middle shaft portion and the middle shaft section ; and a leading end portion provided below the lower middle shaft portion and formed in the bullet shape, and a lower middle shaft portion having a uniform diameter which is smaller than a diameter of the middle shaft section ; a lower taper portion provided between the lower middle shaft portion and the middle shaft section ; and a leading end portion provided below the lower middle shaft portion and formed in the bullet shape, and wherein a taper angle (θ1) of the taper portion is within a range from 2 to 5 degree. <EOS>