An apparatus for measuring an inferior-and-superior-limb blood-pressure index of a living subject, including an inferior-limb blood-pressure measuring device which measures an inferior-limb blood pressure of an inferior limb of the subject, a superior-limb blood-pressure measuring device which measures a superior-limb blood pressure of a superior limb of the subject, an inferior-and-superior-limb blood-pressure index determining device for determining the inferior-and-superior-limb blood-pressure index based on the inferior-limb blood pressure measured by the inferior-limb blood-pressure measuring device and the superior-limb blood pressure measured by the superior-limb blood-pressure measuring device, a heartbeat-synchronous-signal detecting device which detects a heartbeat-synchronous signal that is produced from the subject, a pulse-period-related-information obtaining device for obtaining, based on the heartbeat-synchronous signal detected by the heartbeat-synchronous-signal detecting device, pulse-period-related information that is related to a pulse period of the subject, and a neuropathy-related-information obtaining device for obtaining, based on the pulse-period-related information obtained by the pulse-period-related-information obtaining device, neuropathy-related information that is related to diabetic neuropathy.