PROBLEM TO BE SOLVED: To provide a hemostatic instrument capable of expanding and decompressing an expansion part with a simple operation without using a dedicated instrument separate from a hemostatic instrument.SOLUTION: A hemostatic instrument 10 includes: a belt body 20 wound around a puncture site P of a wrist W; fixing means 30 fixing the belt body in a state of being wound around a wrist; an expansion part 40 connected to the belt body and expanding by injection of air thereinto; and a pressure pump 70 communicating with the expansion part and capable of injecting air outside the expansion part into an expansion space 40a within the expansion part. The pressure pump includes: a roller 71 including a rotary shaft C1 and a spiral projection 71g; and a stator part 72 including a lumen 72a in which the roller is arranged. In the pressure pump, when the roller is rotated, the roller performs eccentric motion with respect to an axial center C2 of the stator part while rotating and thereby moves air outside the expansion part into the expansion space.SELECTED DRAWING: Figure 2【課題】止血器具とは別体の専用の器具を使用することなく、簡単な操作で拡張部の拡張および減圧を行うことが可能な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に巻き付けるための帯体20と、帯体を手首に巻き付けた状態で固定する固定手段30と、帯体に連結され、かつ、空気を注入することにより拡張する拡張部40と、拡張部と連通し、かつ、拡張部の外部の空気を拡張部内の拡張空間40a内に注入可能な加圧ポンプ部70と、を備え、加圧ポンプ部は、回転軸C1を有し、かつ、螺旋状の凸部71gを有するローラー部71と、ローラー部が配置される内腔72aを有するステータ部72と、を有し、加圧ポンプ部は、ローラー部を回転させた際、ローラー部が回転しつつ、ステータ部の軸心C2に対して偏心運動を行うことで、拡張部の外部の空気を拡張空間内へ移動させる。【選択図】図2