Plastic injection moulding is commonly used for manufacturing industry to produce plastic products. The study were carry out for warpage optimisation during injection moulding process. Warpage happen when the moulded products warps immediately where the mould cavity should be straight. In this study, hair dryer nozzle were used to perform the analysis by using Response Surface Methodology (RSM) in Design Expert 7 software and Bat Algorithm (BA) in MATLAB software. Therefore, the mould temperature, melt temperature, packing pressure and cooling time were selected as processing parameters in reducing the warpage. The results showed minimisation of warpage value in y direction. Hence, the result shown that BA method reduce the warpage value from 0.1864 mm to 0.12939 mm.
