The invention discloses a novel paperboard steam spraying device, and belongs to the technical field of spraying equipment for paperboard manufacturing. The novel paperboard steam spraying device comprises a steam spraying device body, wherein the steam spraying device body comprises an inner pipe, a middle-layer pipe and an outer pipe; the inner pipe is a hollow body with an opening in one end, the one opening end of the inner pipe is provided with a steam pipe connector, a plurality of first spraying holes are formed in the outer surface of the inner pipe, the inner pipe is arranged in the middle-layer pipe, and the inner pipe and the middle-layer pipe are coaxially and fixedly connected; the middle-layer pipe is a conical pipe, the middle-layer pipe is arranged in the outer pipe, and the middle-layer pipe and the outer pipe are coaxially arranged; and a plurality of second spraying holes are formed in the outer surface of the outer pipe. According to the novel paperboard steam spraying device, the three layers of tubular structures are used in a mutual cooperation mode, so that the purpose of manually or automatically adjusting the width of a steam outlet is achieved according to the width specification differences of actually-produced paperboards on a production line.