PURPOSE: To increase a head speed by forming the cross-sectional area shape of a hosel section with the blade shape of a projected surface on the side of a heel and a recessed surface on the side of a toe, and by opening the blade section of the toe side recessed-surface of the blade shape at a constant angle externally against the direction of hitting.

CONSTITUTION: The cross-sectional area shape of a central section in the height direction at least at a hosel section 2 formed on the side of the heel 1a of a head main-body 1 is formed with the blade shape of a projected surface 21 on the side of the heel 1a and a recessed surface 22 on the side of a toe 1b, and the chord a-a of the toe side recessed-surface 22 of the blade shape is opened at a constant angle α (for example, 25°≤α≤40°)externally against the hitting direction c-c. As this result, a horizontal force bearing with air current at the time of swing can be prevented from being generated, and a head speed can be increased.