To provide a golf club allowing a change of an insertion depth of a shaft case, and to provide a shaft insertion depth change method for the same.

A golf club is installed with a shaft 4 to a hosel 3 of a head 1 through a shaft case 5 and a bolt 7. The shaft case 5 is fixed to the tip of the shaft 4 by use of an adhesive. A key part 5c is provided in a small-diameter cylindrical part 5b of the shaft case 5. A spacer 10 having slits 11-14 is installed in an inner part inside the hosel 3. Depths of the slits 11-14 are different, and an insertion depth of the shaft 4 is changed by changing the slit engaged with the key part 5c.