Abstract: On a roller leveler the deflection of a plate under the action of levelling rollers is assumed that the deflection is resulting from the forces exerted by both screw-down and bending roller. Based on the elastoplasticity theory of a beam, the bent plate is referred to as a bent beam with the entry intermesh also considered and, generally, about 80% of plate thickness is of plastically deformed layer and 5%-15% or the rest is regarded as due to the effect of bending roller. Different roller bending models are thus developed on beam deflection basis to solve quantitatively the bending of levelling rollers. The roller's bending calculated theoretically conforms with the set value, which reveals the practicality of those models.