Designing in sand casting is a critical activity for manufacturing. Further, activities like cavity design, cavity layout and design of gating system are essential in design. Design of gating system in sand casting is dependent upon a various parameters. Gating system design requires lot of manual input and a number of iterations to finalize the design. This requires a good knowledge of casting process, making this activity completely dependent on the user. In present day industry, lot of CAD/CAM tools are applied for design, development and manufacturing. However, need of sand casting expert throughout design and manufacturing makes it a quite lengthy process. Gating system design being one of the major activities also takes much time. Therefore, it would be quite beneficial to develop a system for automated generation of gating system. Proposed system takes CAD file of the die casting part as input and uses sand casting process, machine and alloy knowledge to determine different parameters for the gating system. Designs of the components of the gating system like runner, gate and overflow have been attempted. A feature library has been proposed as a part of this work which together with parametric design of the gating system generates CAD model of the components of the gating system. The system would go a long way in bridging the gap between designing and manufacturing of die-casting.