PROBLEM TO BE SOLVED: To provide a tourniquet device capable of expanding an expansion part without using a different dedicated device, and capable of preventing a site at which bleeding should be stopped from being unintentionally unnecessarily excessively pressed.SOLUTION: A tourniquet device 10 includes: a belt body 20 to be wound around a puncture site P of a wrist W; fixation means 30 for fixing the belt body in a state in which the belt body is wound around the wrist; an expansion part 40 that is connected to the belt body and expands by being injected with gas; and an injection part 70 capable of injecting gas into the expansion part. The injection part is arranged on the belt body and is capable of being folded so as to reduce a space formed inside the injection part.SELECTED DRAWING: Figure 6【課題】別体の専用の器具を用いずに拡張部を拡張可能であって、かつ、止血すべき部位を意図せずに必要以上に圧迫するのを防止できる止血器具を提供する。【解決手段】止血器具10は、手首Wの穿刺部位Pに巻きつけるための帯体20と、帯体を手首に巻きつけた状態で固定する固定手段30と、帯体に連結され、かつ、気体を注入することにより拡張する拡張部40と、拡張部に気体を注入可能な注入部70と、を備え、注入部は、帯体に配置されており、かつ、注入部の内部に形成される空間を小さくするように折り畳み可能である。【選択図】図6