According to an aspect of this invention, a golf club head includes: a head main body; and a weight material detachably mounted in a weight material mounting portion in the head main body, an external screw thread on the weight material meshing with an internal screw thread in the weight material mounting portion, wherein: the weight material comprises a head portion having the external screw thread and a rod portion which projects from the head portion; and the internal screw thread is provided on an entrance side and a cylindrical portion is provided on a deeper side for engagement with the rod portion in the weight material mounting portion.