PROBLEM TO BE SOLVED: To provide a medical device provided with a balloon, the balloon in which the metal thin film on the surface is less likely to be peeled off and damaged even when the balloon is expanded and contracted, and the medical device provided with the balloon. SOLUTION: The balloon is used for a medical device, in which a metal thin film is laminated on the surface of the balloon base material, the metal thin film is wrinkled, and the recess of the metal thin film and the surface of the balloon base material are adhered to each other. balloon. The thickness of the metal thin film is preferably in the range of 100 to 900 nm. [Selection diagram] Fig. 2【課題】本発明は、バルーンを備えた医療器具において、バルーンを膨張収縮させても、表面の金属薄膜が剥離欠損しにくいバルーン、およびそれを備えた医療器具を提供することを目的とする。【解決手段】医療器具に用いられるバルーンであって、バルーン基材の表面に金属薄膜が積層され、金属薄膜が皺状であり、金属薄膜の凹部とバルーン基材の表面とが接着しているバルーン。金属薄膜の厚さが１００～９００ｎｍの範囲であると好ましい。【選択図】図２
