The present invention provides a pulse wave velocity measurement method and system as well as an imaging device available for everyday use by general users at low cost with measurement accuracy less affected by posture or the like. The present invention simultaneously images different parts of a human body in a non-contact state by a single visible light camera and acquires continuous time series image data. Then, the present invention detects each pulse wave from the image data in the different parts of the human body based on a temporal change in pixel value of the different parts of the human body, and then calculates a pulse wave velocity of the human body based on a time difference between the pulse waves in the different parts of the human body.