Pipes with non-circular cross sections made by reshaping processes are widely used as structural elements in almost all industries. Despite a long history of the process, because of the complicated deformation behavior of pipes during reshaping, the design procedures for forming rolls and pass-schedules mainly rely on experience-based knowledge. Thus, the fundamental and systematic approaches to the reshaping technology and the guidance for the design of rolls and processes have been required. In order to solve these serious problems, a new design method has been developed to determine ideal roll profiles and roll arrangement for the process. It is based on the simulation technique to analyze two-dimensional elasto-plastic deformations of the cross sections of pipes. Furthermore, it is shown that there are good agreements between the results of the design method and the experimental results for the square and the oval pipes.