PROBLEM TO BE SOLVED: To provide a method or the like for manufacturing a diameter-reduced stent easy to install to a delivery catheter.SOLUTION: So as to manufacture the diameter-reduced stent 29, this method includes processes of: disposing a stent 29 in a stent crimping device reducing a diameter of the stent 29 by pressing the stent 29 from the outside inserting a mandrel 19 (a shaft 11 in other words) into the stent 29 and reducing the diameter of the stent 29 from a first outside diameter in a diameter enlargement state to a second outside diameter in a diameter reduced state.
