To stabilize the carry of a hit ball by shortening the centroid positions and hitting heights of iron golf club heads and increasing the inertia moments thereof.

The centroid height positions of the respective clubs relating to the long irons of shaft numbers 2 to 4, the middle irons of shaft numbers 5 to 8 and the short irons of shaft numbers 8 and below are respectively set at <20.5, 20.5 to <22 and ≥22. The longitudinal inertia moments of the respective clubs are respectively set as ≥590 g.cm2, ≥620 g.cm2, and ≥660 g.cm2.