A manufacturing method of an iron-type golf club head has acts of preparing a formed bar-shaped steel substrate, rough-hot forging the bar-shaped steel substrate, mid-hot forging the rough blank, fine-cold forging the mid-blank, cold stamping the striking surface and drilling a hosel of the iron-type golf club head. The cold forging reduces the thermal expansion and contraction of the blank, and the shape of the forged blank is more accurate therefore. As a result, the following grinding processes of the blank are reduced. Therefore, the weight of the blank is more accurate, and the manufacturing time and cost are also reduced. The blank does not have to be heated to high-temperature state prior to cold forging so that the blank can be cooled down faster, and the cost of the heating is reduced.