PROBLEM TO BE SOLVED: To provide a balloon catheter which can reliably shrink a balloon after expanding it and makes it easy to collect balloons after use.SOLUTION: A balloon catheter 10 has: a long shaft part 20； a balloon 30 which is folded on an outer peripheral surface of a distal part of the shaft part 20 and can expand by fluid being flown inside； and at least one ring-shaped shrink auxiliary part 60 which encircles a part of an axial direction on an outer peripheral surface of the folded balloon 30 in a peripheral direction and has greater stretchability than the balloon 30. At least one part of the peripheral direction of the shrink auxiliary part 60 can slide with respect to the balloon 30, and in the state that the balloon 30 is expanded, the shrink auxiliary part 60 generates a shrinking force by expanding longer than natural length.SELECTED DRAWING: Figure 1【課題】バルーンを拡張させた後に確実に小さく収縮でき、使用後の回収が容易となるバルーンカテーテルを提供する。【解決手段】バルーンカテーテル１０は、長尺なシャフト部２０と、シャフト部２０の遠位部の外周面に折り畳まれて設けられ、内部に流体が流入することで拡張可能なバルーン３０と、折り畳まれたバルーン３０の外周面の軸方向の一部を周方向に囲み、バルーン３０よりも伸縮性が高い少なくとも１つのリング状の収縮補助部６０と、を有し、収縮補助部６０の周方向の少なくとも一部は、バルーン３０に対して摺動可能であり、バルーン３０を拡張させた状態において、収縮補助部６０は、自然長よりも長く伸長して収縮力を発生する。【選択図】図１
