PROBLEM TO BE SOLVED: To make it possible to improve the measurement accuracy in a configuration having a first fluid bag and a second fluid bag contained inside the first fluid bag.SOLUTION: A blood pressure information measurement device comprises: a cuff including a first fluid bag and a second fluid bag contained inside the first fluid bag； a pressure increase/decrease mechanism for increasing and decreasing the pressure in an internal space of the first fluid bag and the pressure in an internal space of the second fluid bag； a control unit for controlling the operation of the pressure increase/decrease mechanism； a pressure detection device for detecting the internal pressure of the first fluid bag； and a calculation unit for calculating a blood pressure based on the blood pressure information detected by the pressure detection device. When calculating the blood pressure information, the control unit controls the operation of the pressure increase/decrease mechanism such that the internal space of one of the first fluid bag and the second fluid bag is pressurized and inflated until the internal pressure of the one fluid bag reaches a predetermined pressure, and then pressurizes and inflates the internal space of the other fluid bag of the first and second fluid bags, while maintaining the one fluid bag in a sealed state.SELECTED DRAWING: Figure 6【課題】第１流体袋と、当該第１流体袋に収容される第２流体袋とを備えた構成において、測定精度を向上させることができる。【解決手段】血圧情報測定装置は、第１流体袋、および第１流体袋の内部に収容された第２流体袋を含むカフと、第１流体袋の内部空間および第２流体袋の内部空間を加減圧する加減圧機構と、加減圧機構の動作を制御する制御部と、第１流体袋の内圧を検知する圧力検知装置と、圧力検知装置にて検知された圧力情報に基づいて血圧を算出する演算部と、を備える。血圧情報を算出する際に、制御部は、加減圧機構の動作を制御することにより、第１流体袋および第２流体袋のうち一方の流体袋の内部空間を加圧して膨張させることで一方の流体袋の内圧が所定の圧力に到達した後に、一方の流体袋の密閉状態を維持しつつ第１流体袋および第２流体袋のうち他方の流体袋の内部空間を加圧して膨張させる。【選択図】図６
