Because of a growing globalization and a more dynamic competition, it is necessary to produce with greater efficiency and to promote new developments. The aim within this work was to optimize the production process of an aluminum casting part with the aid of numerical simulation. First of all, filling and solidification of the existing process were simulated. The gained experiences were directly incorporated into a new process development. Next to the qualitative improvement of the casting parts, the focus was set on cost savings. The comparison between practical trials and the simulations led to a better understanding regarding the significance of the different factors influencing the simulation of the casting method. The gained experiences were included in the new process development, whereby significant cost savings and an increase in productivity were reached. Further, the required energy input to produce a casting part was considerably reduced.