The burning of crop straws polluted environment due to lack of high efficient and rapid industrialization processing measures for straws in the producing area. Based on roller forming principle and theory for straw with no mold, a technical solution was put forward, including roller rolling, high pressure and cold forming. During the experiment of key performance parameters on the multiroller forming for straws, corn straws with different moisture contents from 9% to 23% and size of no more than 12mm were used to study their compression properties by an universal testing machine with neither a mold nor a closed state. The curves of compression properties were obtained. Yielding phenomenon was found during the compression procession and the compression process can be divided into four stages which were the loose stage, pressed stage, yielding stage and forming stage. Meanwhile, the compression yield limit of corn straws was decreased with the increase of moisture content. Briquette thickness test of straw with moisture content of 9% at various compression levels verified the roller forming principle, and it also provided design basis about the compression ratio for multistage roller forming device. Finally, based on the principle of roller rolling and forming and the compression properties of straws, a multistage roller forming device for straw by using feed rollers, compression rollers and forming rollers was designed, which can meet the requirements of efficient and industrial production technology in the producing area.