This paper deals with the application computer-aided engineering integrated with statistical techniques to reduce warpage variation due to injection molding process parameters during the production of thin-shell plastic components. For this purpose, Moldflow simulation runs are carried out by utilizing the combination of process parameters based on a three-level L(18) orthogonal array table. An optimal parameter combination of the injection molding process is obtained via grey relational analysis (GRA). By analyzing the grey relational grade matrix, the degree of influence for each controllable process factor onto warpage can be found. Additionally. the analysis of variance (ANOVA) is also applied to identify, the most significant factor, the melt temperature and the packing pressure are found to he the most significant factors in the simulation process for an injection molding process of thin-shell plastic parts.