This paper mainly focuses on the design phase for the die for an automobile component made of aluminum alloy (AIDC12). The design phase for the casting die involves discrete selection of design parameters namely, gate area, gate velocity, position of air vents and also the nature of defects in the casting. Work involves designing the Casting die while securing crucial inputs from the 'flow simulation' for the casting. The analysis would highlight the problem areas in the geometry and the probable locations where the process defect is likely to occur.