Abstract: Since there is no accurate mathematical model, the straightening force is usually determined by worker's experience and repeated experiments when tubes and bars are straightened by the rolls with equal curvature. Aiming at this problem, a straightening force model was established on the basis of the principle of mechanical equivalence, and then the equal curvature straightening process was visually simulated by the ANSYS/LS-DYNA. The results confirmed by local experiments is shown to be valid and receivable. The key parameters under different conditions of the model were determined by visual simulations, which may make the model applicable in different situations.