A wearable device includes a blood pressure sensor configured to continuously measure blood pressure of a measurement subject; a check section configured to, in response to an instruction for commencing a continuous measurement of the blood pressure, check whether a treatment device to be used during the continuous measurement of the blood pressure is attached to the measurement subject; a measurement controller configured to, when the check section confirms that the treatment device is attached, execute a continuous measurement of the blood pressure with the blood pressure sensor; and a display section configured to, when the check section does not confirm that the treatment device is attached, display a form of guidance to prompt attachment of the treatment device.