Abstract: A decorative string control box, comprising a casing covered with a cover and a cap with a decorative string control circuit board fastened therein for fastening a plurality of decorative string conductor terminals. Each decorative string conductor terminal can be conveniently inserted through the wider left half part of each mounting slot at one end of the cover and pulled outward to engage in a recessed portion on the back side of the narrower right half part of each mounting slot and then firmly pressed by the cap in a position to electrically contact a corresponding contact on the decorative string control circuit board.