A blood pressure information display device for calculating a blood pressure value based on a pulse wave amplitude through the oscillometric method and the like, and displaying the calculated blood pressure value as blood pressure information performs a process of changing a magnitude of a specified pulse wave amplitude of a plurality of extracted pulse wave amplitudes according to the operation by a user (medical staff) when a predetermined instruction is input. A predetermined algorithm is applied to the plurality of pulse wave amplitudes reflecting the change to calculate a reference blood pressure value, and the calculated reference blood pressure value is displayed as the blood pressure information.