Abstract. The electronic key is widely used in our life due to its small volume, tempting color, beautiful shape and easily portability. In order to shorten the design cycle and reduce the test cost of mold for the shells of electronic key, the work should be done firstly to analyze the injection technique. The electronic key shell is analyzed by using Finite Element Method (FEM) to judge reliability of the structure. Static structural and explicit dynamics analysis are conducted. The results provide valuable reference for the structural optimization design. Injection moulding process of the shell is simulated by applying Moldflow. Results show that the shrinkage is too small, the average value 0.12 mm and maximum value 0.497mm, to neglect the negative effect on forming parts after the injection. Furthermore, the designed mold structure was reasonable, which meet the demand of injection practically.