Abstract: The present invention relates to a curl-shaping device for paperboard, including: a conveying part adapted to convey the paperboard; a compressing part adapted to compress the top surface of the paperboard; a curl-shaping part disposed at the side of the conveying part to form a curled portion along the lateral side of the paperboard; a natural cooling and shaping part formed at the front portion of the curling-shaping part to fix the curled portion again; and a paperboard lateral side guide disposed at the opposite side to the curling-shaping part to push the opposite lateral side to one lateral side of the paperboard where the curled portion is formed.