A blood pressure information measurement device includes a servo control unit for performing a servo control of a pressure adjustment unit so that a value of an arterial volume signal matches a control target value and a fluctuation detection unit for detecting rapid fluctuation of the arterial volume signal at an initial stage during a period of the servo control. The fluctuation detection unit determines that the rapid fluctuation occurred when a control deviation representing a level of the arterial volume signal having the control target value as a reference becomes greater than or equal to a predetermined magnification of a reference deviation. The blood pressure information measurement device further includes an adjustment processing unit for adjusting a control amount of the pressure adjustment unit by the servo control unit so that an excessive response is not made when the rapid fluctuation is detected by the fluctuation detection unit.