To provide a method of manufacturing metal golf club heads of all numbers by cutting a block of iron having a required height, width and length, and to provide metal golf club heads manufactured by the method.

The method of manufacturing metal golf club heads includes: a chucking step in which a block of iron having required height, width and length is chucked in a cutting machine; a cutting step in which the block of iron is three-dimensionally ground by a cutting machine; and a finishing step in which projections left in the preceding cutting step are removed. The invention includes: a manufacturing method which is capable of manufacturing metal golf club heads of all numbers by cutting from one block of iron; a manufacturing method of a metal block in a club head unit in which the block of iron is formed into a prescribed shape by any one method of casting, forging or extruding; and a means of manufacturing the metal golf club heads manufactured by the foregoing methods.