The hole-flanging process of conical punch was simulated by using finite element software Dynaform. Different flanging limit coefficients were obtained by changing the blank thickness and cone angle. By comparing，the results show that conical punch can improve the limit deformation degree at the right angel range than cylindrical convex punch, also the influence law of sheet thickness and cone angle on the flanging limit is given. When the blank thickness is constant, the flanging limit coefficient shows a trend of decreasing first and then increasing with the cone angle changes; when the cone angle is constant, the flanging limit coefficient decreases with the blank thickness being increased.