In deep drawing process, the experimental approach to obtain proper die-face design is not only expensive, but also requires much time and effort. Numerical simulation of the die-face design using expansion ratio analysis (ERA) can provide an avenue for lowering the cost and increasing the speed of the design process. A finite-element model of four-node quadrangle element is developed based on static implicit method using the Finite Element Code Marc. By the use of the model, the die-face design of oil pan deep drawing process is simulated. The relationship between the ERA and the maximum thickness variation is obtained. The smaller the ERA, the smaller the maximum thickness variation can be acquired. The mission success rate of the forming process increases, too. All the simulation results show reasonable agreement with the experiment.