A blood pressure measuring method and system. The method includes: obtaining at least one video that captures a first body area and a second body area of a testee extracting multiple gray scale values for corresponding images that capture the first body area and multiple gray scale values for corresponding images that capture the second body area drawing a pulse-wave waveform of the first body area based on the multiple gray scale values of the first body area, and drawing a pulse-wave waveform of the second body area based on the multiple gray scale values of the second body area determining a pulse-wave propagation time based on the pulse-wave waveform of the first body area and the pulse-wave waveform of the second body area and obtaining a blood pressure value of the testee based on a corresponding relation between the pulse-wave propagation time and blood pressure.
