Three Dimensional Molded Interconnect Devices (3D-MID) has enormous potential for rationalization in both manufacturing process and the freedom to design of mechatronic products. Two shot molding is one of the most important and commonly used methods among the various MID manufacturing processes. Currently, there is a lack of effective design and simulation tools that can be used for MID with two shot molding. In this paper, an integrated product model using feature technology, some MID-specific design functions, and one special interface based on the API of Moldflow Plastics Insight (MPI) and the COM-Technology are presented. These developed product model, functions and interface increase the efficiency of the MID design process, and the design and simulation integrated environment also towards the rational and optimal design of MID products with two shot molding.