To provide a metal pin clasp buckle which achieves higher safety in handling or when contact occurs with a finger, an arm, clothing or the like of a user or other persons and better durability of a retaining function by elastic engagement with a mating hole without affecting the intrinsic function of a metal pin clasp buckle at all.

A frame 1 for forming a buckle thereon made up of a brass member is formed rectangularly with a horizontal support frame 1a and a horizontal receiving frame 1b as opposed to each other and two vertical frames 1c as opposed to each other alike. A rear end part of a fastening pin 3 in which a tip part containing a tip where a lock hole 3a and a lock recess part 3b are formed is covered with a cover body 4 comprising a vinyl chloride resin and is bound so loosely on the horizontal support frame 1a that it turns surely and the tip part of the fastening pin 3 is received on the horizontal receiving frame 1b.