The invention relates to a special device for mixing, plasticizing and rolling ultra-high molecular weight polyethylene powder and extruding into a strip-shaped thermal-plasticized material. The device is able to supply the strip-shaped thermal-plasticized material to a mini or small-type precision rolling production line for continuously producing diaphragm materials. The device comprises rotors, a temperature control device, a visual cylinder, flanges, racks of which two ends are supported, and other parts; each rotor is divided into four parts, namely, an oblique tooth engaging section, a buffering section, a rolling section and a stopping section; firstly, the material is fed through a feeding opening and then processed by mixing, plasticizing and fusing in the rotor engaging section; secondly, the material is buffered through a buffering groove in the buffering section of each rotor in order to change the flowing direction; and thirdly, the material is rolled through a roller at the rolling section and then extruded to be the strip-shaped material under the matching of the stopping section. Compared with the prior art, the device has the advantages that the processes of preheating and mixing, fusing and plasticizing, and rolling and extruding of the material can be finished once, thus the safe and reliable continuous production can be realized, and the production efficiency is greatly raised; in addition, the device is simple in structural design, and convenient and fast to operate.