A punch die comprising: a punch body comprising a punch edge portion at a lower end portion along an axis, a key projecting from an outer periphery, and a punch driver at an upper portion along the axis; a punch guide comprising an inner hollow elongated along the axis and receiving the punch body to be movable along the axis, and a keyway formed on an internal periphery of the inner hollow to extend along the axis and mesh with the key ; a retainer collar rotatably combined with the punch guide at an upper end along the axis and around the axis, the punch driver passing through the retainer collar to be movable along the axis; a punch head screwed in an upper end portion along the axis of the punch driver to regulate a position of the punch driver; an elastic member interposed between the punch head and the retainer collar to bias the punch driver upward along the axis; a circular opening formed on an upper surface along the axis of the punch guide and wider than the inner hollow of the punch guide ; and a press-button movable in a radial direction relative to the axis, and biased outward, characterized in that: the circular opening of the punch guide comprises a plurality of dent portions being dented radially outward relative to the axis from an internal periphery of the circular opening and being mutually circumferentially spaced; and the press-button is supported by the retainer collar and comprises an engaging portion capable of engaging with any of the plurality of dent portions and, when the press-button is pressed radially inwardly, disengages from a dent portion to allow rotation of the punch guide along with the punch body relative to the retainer collar . a punch body comprising a punch edge portion at a lower end portion along an axis, a key projecting from an outer periphery, and a punch driver at an upper portion along the axis; a punch guide comprising an inner hollow elongated along the axis and receiving the punch body to be movable along the axis, and a keyway formed on an internal periphery of the inner hollow to extend along the axis and mesh with the key ; a retainer collar rotatably combined with the punch guide at an upper end along the axis and around the axis, the punch driver passing through the retainer collar to be movable along the axis; a punch head screwed in an upper end portion along the axis of the punch driver to regulate a position of the punch driver; an elastic member interposed between the punch head and the retainer collar to bias the punch driver upward along the axis; a circular opening formed on an upper surface along the axis of the punch guide and wider than the inner hollow of the punch guide ; and a press-button movable in a radial direction relative to the axis, and biased outward, characterized in that: the circular opening of the punch guide comprises a plurality of dent portions being dented radially outward relative to the axis from an internal periphery of the circular opening and being mutually circumferentially spaced; and the press-button is supported by the retainer collar and comprises an engaging portion capable of engaging with any of the plurality of dent portions and, when the press-button is pressed radially inwardly, disengages from a dent portion to allow rotation of the punch guide along with the punch body relative to the retainer collar . the circular opening of the punch guide comprises a plurality of dent portions being dented radially outward relative to the axis from an internal periphery of the circular opening and being mutually circumferentially spaced; and the press-button is supported by the retainer collar and comprises an engaging portion capable of engaging with any of the plurality of dent portions and, when the press-button is pressed radially inwardly, disengages from a dent portion to allow rotation of the punch guide along with the punch body relative to the retainer collar . <EOS>