The purpose of the present invention is to provide a sphygmomanometer that has a high level of measurement accuracy and places a low burden upon a subject whose systolic pressure is being measured. To this end, the sphygmomanometer according to the present invention is characterized by comprising: a cuff pressure and pulse wave detecting unit that detects cuff pressure and pulse waves； and a blood pressure calculating unit that divides pulse waves detected by the cuff pressure and pulse wave detecting unit into a plurality of sections within a specific period, and calculates an estimated value for systolic pressure on the basis of fluctuations in the symmetry of the pulse wave waveform in the plurality of sections, said fluctuations occurring along with variations in the cuff pressure detected by the cuff pressure and pulse wave detecting unit.
