The medium-thick sheet metal extrusion has been a typical bulk forming feature used in the sheet metal forming industry while there isn’t enough know-how available. Therefore, the sheet metal extrusion process was simulated in this study by using an arbitrary Lagrangian-Eulerian (ALE) finite element method implemented in MSC. Marc. Firstly, the simulation results are compared with experimental data from a reference to verify the usefulness of the simulation. Then, based on the simulation results, some phenomenological characteristics of the sheet metal extrusion process, such as the material flow, shrinkage cavity and the effect of area reduction on the forming force, are present. The work presented in this paper might be used for as design fundamental of the sheet metal extrusion process.