At present, Lost Foam Casting (LFC) is one of the foundry processes preferred to manufacture intricate geometry, narrow dimensional tolerances and good superficial finished. Cobral Ltda. is a metal-mechanic sector’s company located in Medellin City and since the year 2000 is dedicated to produce automotive parts in grey and nodular iron by LFC process. However, from the process was starting up, high percentages of rejection was obtained, between 20% and 50%. The study of the process variables and their proper control in the different stages, allowed the rejection percentages minimization and an increase in the plant productivity. The LFC process stages and some relevant aspects about the optimization that was carried out, are described.