A golf club having a face adapted to directly strike a golf ball thereon, a pipe-shaped shaft coupled to the club head, and a grip coupled to the top end periphery of the shaft, includes a first protrusion formed on one side of an internal surface of a face thereof; a second protrusion formed on the rear surface of the interior thereof in such a manner as to face the first protrusion and having a lubricating oil inlet passage formed thereon in such a manner as to be connected to the outside; a spring disposed engagedly between the first protrusion and the second protrusion; a bolt detachably mounted on the entrance of the lubricating oil inlet passage of the second protrusion; and an elastic structure slidingly operating along the spring in such a manner as to surround the spring.