Abstract: This process may result in high labor and material costs. The adjusting machine parameters of injection molding for a car storage box were optimized by the orthogonal experiment and mold flow analysis. The optimum combination of process parameters for injection molding was obtained based on the two performance indexes of volume shrinkage and y-direction warpage. The most important parameters affecting the two performance indexes were the holding pressure and melt temperature, which should be adjusted first during the injection molding process. Injection molding production revealed that the injection-molded products were successfully confirmed and accepted by manufacturers. These results proved that the parameters for a certain performance index of plastic part could be effectively adjusted by using orthogonal experiment, and this method had a promising application prospect for other plastic and mould companies.