An electronic sphygmomanometer includes a cuff containing an air bladder, an air charger, an air discharger, a pressure sensor, a memory a display, and CPU for executing programs stored in the memory and calculating a blood pressure value based on the pressure changes within the air bladder. The CPU further includes an estimation processing part for calculating an estimated blood pressure value based on the pressure change within the air bladder during the inflation of the air bladder at a first rate, a measurement processing part for measuring a blood pressure value based on the pressure change within the air bladder during the deflation of the air bladder at a second rate, and a determination processing part for comparing the estimated blood pressure value with the reference blood pressure value and determining whether the estimated blood pressure value is within a predetermined range from the reference blood pressure value.