To provide the slag float preventing method for punching die, a die using the method and the method/device for producing the die which is usable even for a small diameter punch and is capable of punching a precise shape.

In this slag float preventing method for punching die, the slag floating is prevented by providing plural grooves 9 on the inner face of a through hole 3 at the position lower than the surface 7 of a die 1 and by engaging punched slag to a projecting part of an edge part of the grooves. This device 30 for producing punching die is provided with a work table 33 which is inclined at an arbitrary angle against an optical axis of a laser beam emitted from a laser beam machining head 37 of a laser beam machine 31 and is rotated/indexed at an arbitrary angle to machine plural grooves having a projecting part to an edge of the grooves 9 on the inner face of the through hole 3 of the die 1 placed on the work table 33.