A disposable electrode includes: an electrode pad and a connector, connecting the electrode pad to a defibrillator, and including an information holder that can be provided with a transmissive opening or a light reflective member, the information holder holding information about at least an expiration date, depending on presence or absence of the transmissive opening or the light reflective member, the information holder allowing the information to be notified from the defibrillator when the connector is connected to the defibrillator.