To improve the abrasion resistance of a bit for a shield machine, and to lengthen the lifetime by fixing superabrasive to the edge section of the bit for the shield machine.

Superabrasive 3 such as diamond abrasive is fixed to the edge section 2 of the base metal 1 of the bit for the shield machine. The base metal 1 is degreased, a section, to which the superabrasive 3 of the base metal 1 is not fixed, is masked, the base metal 1 is introduced into a plating tank, and the surface not masked of the base metal 1 in the plating tank is filled with the superabrasive 3. A cathode is connected to the base metal 1, an anode is joined with a plating solution and electricity is conducted and plating is performed, superabrasive 3 is fixed temporarily and the base metal 1 is pulled up from a plating bath once, excess superabrasive is removed and the base metal 1 is dipped again and plating is continued, and superabrasive 3 is fixed to the base metal 1. Nickel having large roughness and hardly damaging a superabrasive 3 layer at the time of excavation works is proper as a metal used for plating. The abrasion resistance of the bit for the shield machine is improved by protecting an edge by the superabrasive 3 layer.