A blood pressure measurement method includes specific steps. Sample and store photoplethysmography signals and electrocardiosignals. Measure blood pressure to get a plurality of values of systolic blood pressure and diastolic blood pressure. Synchronize the electrocardiosignals and the photoplethysmography signals, and calculate a time interval between an electrocardiosignal feature point and a photoplethysmography signal feature point. Establish a formula for calculating the value of the systolic blood pressure: SBP=a1×PWV+b1×BMI+c1. Establish a formula for calculating the value of the diastolic blood pressure: DBP=d1×SBP+e1. Put the time interval between the electrocardiosignal feature point and the photoplethysmography signal feature point into the formula for calculating the value of the systolic blood pressure. Put the value of the systolic blood pressure into the formula for calculating the value of the diastolic blood pressure.
