Abstract: Communication and electronic products have been developing towards the design concept of being light, thin, short and small.To acquire the maximal internal space for parts to be packed closely into the product, one way is to reduce the wall thickness of the housing components.Therefore, the production technique of plastic injection molding of a part with a thin shell feature is becoming more important.Many factors lead to the defects of parts, such as warpage, shrinkage, residual stress, and so on. This research used the experimental design of the Taguchi method to determine the injection molding conditions, and the injection processes were simulated by using the integrated software packages Moldflow^TW.Both molding conditions and affecting factors were discussed regarding the degree of warpage of the shell of a mobile phone.The results showed that the melt and mold temperature had the greatest influence on shrinkage in X direction, the packing time had the greatest influence on shrinkage in Y direction and the packing pressure had the greatest influence on warpage of Z direction.However, the shrinkage and warpage were only slightly influenced by the gate dimension and the injection rate in the case of mobile phone. In addition, applying the experimental design of the Taguchi method is a quite effective method to deduce the optimum set of affecting factors in injection molding to produce plastic parts with minimum shrinkage and warpage.