Abstract: The present disclosure is concerned with a self-retractable rubber nipple or pacifier which is intended to prevent an infant from getting into the habit of sticking to the same even in sleep by slowly retreating it from the mouth thereof without the baby's notice; which is characterized in that a hollow, collapsible pleated bellows-like element is planted on one side of the stop plate of a conventional rubber nipple with the pleated bellows-like element relatively moveable with respect to the elongated nipple member, and an air volume control unit is provided on the stop plate so that air can regulatively flow in the bellows-like element, expanding it to such an extent that the nipple can disengage from the mouth of an infant slowly without his or her notice.