An iron type golf club head is provided with an annular trench including:
an upper side trench portion that is positioned above the horizontal
border line on the face surface through the sweet spot; and a lower side
trench portion that is positioned beneath the above described border
plane, and a ratio (Wu/Wd) of the average trench width Wu of the upper
side trench portion to the average trench width Wd of the lower side
trench portion is in the range of 2.5 to 5.0.