A blood pressure measuring apparatus performs blood pressure measurement of a person to be measured. The apparatus includes: setting a measurement mode including at least a nocturnal blood pressure measurement mode to perform the measurement; and determining whether a blood pressure measurement posture is good under a first determination condition based on a height difference between a position of the apparatus and a heart position of the person in a sitting posture, and under a second determination condition based on a height difference between a position of the apparatus and a heart position of the person in a supine posture. A determination condition of the determining is switched to the second determination condition when the nocturnal blood pressure measurement mode is set.