Abstract: The deformation characteristics are complicated in 3-roll rolling process. The deformation of the workpiece in round-flat pass was simulated with the general FEM software package ANSYS, on the basis of the elastic-plastic deformation theory. The Newton-Raphson method is used to the actual nonlinear result.In order to verify the finite element simulation, the same deformation process was experimentally investigated with the visual-plasticity approach. In the experiment the digital control technology and the laser marking system were used to make the grids, the microscope to enlarge the grids and the computer image analysis system to read the original data automatically. The FEM results agree with the experiment well.