A first and second pulse wave sensor is mounted on the belt in a state of being separated from each other in the width direction. The belt is mounted around the measurement site, the member presses the first and second pulse wave sensors against the measurement site with a predetermined pressing force. Each of the pulse wave sensors detects a pulse wave in a facing portion of an artery passing through the measurement site. The body motion detection unit detects the presence or absence of body motion. When there is no body motion, the control unit sets a force of the pressing member to a pressing force to measure a pulse wave with the sensors. When there is body motion, the control unit sets a force of the pressing member to a second force lower than the first force and higher than zero and interrupts measurement of a pulse wave.
