Abstract: According to the requirements of plastic injection process for controller shell of the motor B5 headlight，such as material，structure feature, and key size, two different gating systems were designed. CAE technology was applied to analyze and compare the weld lines，air holes，locking force, warping deformation, plane stress, and other parameters produced by the two gating systems and finally the first one was chosen. Through mould testing and process parameters adj ustment，it confirmed that the injection temperature was 295 0C，injection pressure was 107 MPa，and packing pressure was 77 MPa. Applying these parameters，the products possessed stable quality and reliable precision.