PROBLEM TO BE SOLVED: To provide a mandrel suitable for manufacturing a high-quality stent easily and in a short time.SOLUTION: A mandrel 10 used for manufacturing a stent 50 is formed by assembling a plurality of mandrel pieces 11. At least one of the plurality of mandrel pieces 11 has a scale SC affixed on its own outer surface 11T. The mandrel includes a mechanism MM to perform a position change or replacement between one mandrel piece 11 and the other mandrel piece 11.