A blood pressure measurement bladder (50) has a predetermined amount of air introduced and sealed therein. A CPU (30) measures in advance the P-V property. The blood pressure measurement bladder (50) is wrapped around a measurement site. By exerting pressure from the outer side to the blood pressure measurement bladder (50), the internal pressure in the blood pressure measurement bladder (50) is increased to exert pressure on the blood vessel. During this process, the cuff pressure in the blood pressure measurement bladder (50) generated by volumetric change of the blood vessel by changing the pressure exerted from the outer side to the blood pressure measurement bladder (50), and the pressure pulse wave data are detected. By adding the cuff compliance property obtained by the P-V property that was measured in advance to the detected data as a correction value of the pressure pulse wave, blood pressure is calculated.
