Abstract A computerized numerical simulation system for cold roll-forming was developed. It was applied to various roll-forming processes of ERW (electric resistance welded) pipes, light gauge section steels, deck-plates and others. Through simulations, effects of pass-schedule, geometry and position of roll, dimension of product and mechanical properties of metal sheet on deformation features of metal sheet at every forming stage, stress and strain occurring in it, roll separating force, roll driving torque and dimensional accuracy of product were clarified. The system is now being used for design and prediction of desirable profiles of forming rolls, roll positions and other operation factors. It is also being successfully used to design pass-schedules for newly requested products.