Abstract: In order to solve the problem that the hole of ring die easy to block due to material accumulation, this paper takes 9 YK-0.4 D ring mode block press as the research object, redesigns the surface structure of the roller, and sets "tooth bulge" on both sides of the outer surface of the roller. The number of parameters is obtained by the design criteria of involute standard straight tooth cylindrical gear. The number of teeth on the roller is 84, and the total tooth height is high In order to make the ring die fit smoothly and improve the hole of the ring die, the geometric relationship between the ring die and the improved press roll is obtained. The groove depth on both sides of the wedge block is 5 mm and the groove width is 1.7 mm. SolidWorks is used for 3D modeling and assembly of the new compression device, and ANSYS is used for flexible body modeling of corn straw. The virtual prototype model of 3D model and flexible body model is established in Adams through rigid flexible coupling. The compression process of corn straw in the compression chamber is simulated and analyzed, and the stress of corn straw under different spindle input speed is obtained. It was observed that the "dentate protrusion" of the pressure roller in the feeding area of the compression chamber mainly promoted the corn straw; in the pre compression process, with the increase of materials and friction, the driving force of the pressure roller on the corn straw changed into rolling friction, and the pressure value increased exponentially; in the main compression process, the extrusion of the "dentate protrusion" could overcome the friction of the hole wall and make the straw smooth at this time, the pressure value fluctuates in a small range and gradually tends to be stable, which can avoid the occurrence of blockage to a certain extent.