The apparatus for feeding closures provided with a tube to an operating unit, has a rotatable disk-like body, having a substantially vertical axis and a fixed or movable wall which delimits the body peripherally. The disk-like body has a circular supporting wall which is permeable to air at an outer annular portion, and is provided with a peripheral annular track adapted to accommodate closures arranged with their tubes directed upward. A pump is provided and arranged below the supporting wall to direct a jet of air with a substantially vertical direction toward a portion of the lower surface of the supporting wall so as to lift the closures from the circular supporting wall and push them toward the peripheral annular track from which closures exit through a passage defined in the wall which delimits the disk-like body.