An applicator cap is closed on the front side and opening on the rear side, covering an applying part provided in the front end of a barrel cylinder of an applicator, from the rear-side opening, and detachably fitted on the barrel cylinder so as to be able to seal and keep the surrounding space of the applying part airtight, and includes a holding portion formed such that the middle part of the cap with respect to the axial direction is smaller in outside diameter than the front end with respect to the axial direction.