Abstract: Due to the size effect, the mechanical properties of ultra-thin stainless steel strips differ from those of conventional strips, and their tensile leveler and processes have unique characteristics. However,the domestic theoretical foundation in this field is weak, and such equipment and process models primarily rely on imports, which severely impacting the production of new varieties and high-quality ultra-thin strips. In this paper, the metallographic structure, mechanical properties, and Bauschinger effect of ultra-thin strip were analyzed. By integrating tensile bending theory with practical applications, a shearing-folding experimental device was developed that simulates repeated loading deformation with small bending radius, created a tension leveller with a minimum thickness of 0.01 mm, width of 200 mm, maximum yield strength of 1 000 MPa and elongation 3%,and a tension leveling model was eatablised. The research methods and outcomes can provide reference for the independent development of a tension leveller for ultra-thin strips.