PURPOSE: To cut a lead with a regularly constant lead length by arranging a lead length holding mechanism consisting of a linear material having a required thickness having a form laid along one cutting blade side surface of a pair of cutting blades.

CONSTITUTION: A lead length holding mechanism 1 using a piano wire is fixed in one end to a hole 4 provided on the back surface side of the rotating shaft 3 of a lead wire cutting tool 2 such as a nipper, and has a form laid along the side surface of one optional cutting blade 5 of a pair of blades 5, 6 opened and closed with the rotating shaft 3 as a supporting point. The middle is passed through a groove 7 provided on the edge side of the rotating shaft 3, and the other end is inserted and fixed to the vinyl cover 9 of a handle 8 continued to the cutting blade 5 along which the piano wire is laid. By changing the diameter of the piano wire, the cutting length of a lead wire can be changed.