PROBLEM TO BE SOLVED: To provide a balloon with a mounting jig, a package, and a method for mounting the balloon, which can reduce the burden on an operator when mounting the balloon on an insertion portion of an endoscope. SOLUTION: A first holding portion 84 holds a portion in which a first tubular portion 60A is folded outward toward a second tubular portion 60B. The first holding portion 84 elastically deforms the first tubular portion 60A into a state in which the diameter is larger than in the natural state. The portion where the first tubular portion 60A is folded outward toward the second tubular portion 60B is a portion where the first tubular portion 60A is turned over and the inner surface is exposed to the outside. Similarly, the second holding portion 86 holds a portion in which the second tubular portion 60B is folded outward toward the first tubular portion 60A. The second holding portion 86 elastically deforms the second tubular portion 60B into a state in which the diameter is larger than in the natural state. In this way, the balloon 100 with a mounting jig is completed. [Selection diagram] Fig. 5【課題】バルーンを内視鏡の挿入部に装着する際の作業者の負担を軽減できる装着治具付きバルーン、包装体、及びバルーン装着方法を提供する。【解決手段】第１保持部８４は、第１筒部６０Ａが第２筒部６０Ｂに向かって外側に折り返された部分を保持する。第１保持部８４は第１筒部６０Ａを自然状態よりも拡径した状態に弾性変形させる。第１筒部６０Ａが第２筒部６０Ｂに向かって外側に折り返された部分とは、第１筒部６０Ａを裏返して内面を外側に露出させた部分である。同様に、第２保持部８６は、第２筒部６０Ｂが第１筒部６０Ａに向かって外側に折り返された部分を保持する。第２保持部８６は第２筒部６０Ｂを自然状態よりも拡径した状態に弾性変形させる。このようにして装着治具付きバルーン１００が完成する。【選択図】図５
