The invention relates to a device for manufacturing a tubular lampshade and a manufacture method. The device comprises an opening die for being installed on a head of an extruder, wherein die cavities for molding a tubular lampshade are arranged in the opening die and connected with material flow channels arranged in the opening die. The device is characterized that the die cavities comprise three parts, namely the independent first molding cavity for molding the transparent part of the lampshade as well as the second die cavity and the third die cavity for molding the residual part of the lampshade, wherein the section of the third die cavity is same with the section of the lampshade to be molded; the two material flow channels are not communicated, an outlet of the first material flow channel is connected with the first die cavity and positioned above the first die cavity, and an outlet of the second material flow channel is connected with the second die cavity and positioned below the second die cavity. The manufacture method comprises the following steps: respectively simultaneously charging transparent prescription materials and opaque prescription materials into different material flow channels and integrally molding the tubular lampshade with a transparent part and an opaque part. Compared with the prior art, the invention can integrally extrude and mold the tubular lampshade with the residual part of the transparent part and the opaque part and has favorable seal effect.